Information educational and cognitive materials. The mechanism of formation of odor traces

§ 1. History of the doctrine of human scent traces

The possibility of using dogs for search and investigative purposes was first pointed out by the Austrian scientist Hans Gross 1 in his guide for investigators. He noted that with the help of a dog one can quickly get on the trail of a criminal. Considering the volatility of odorous substances, he also proposed storing objects that carry odorous traces in tightly closed glass and tin containers.

In Russia, dogs were first used in police service in the Baltic provinces, and in 1907, a police dog kennel was created in St. Petersburg. In the fall of 1908, the Russian Society arose in the capital to encourage the use of dogs for police and guard service, which in 1909 began publishing its own magazine dedicated to dog breeding. In the same year, the society opened a model kennel, dogs for which were purchased in Germany, and a school for trainers.

Experiments with using dogs for detection purposes have been very successful. In 1908, the dog Tsini became famous for its investigative qualities in the Baltic province, and in 1909 the dog Tref became widely known in Moscow.

Issues of the forensic use of human scent traces were raised and developed at different times in the works of T.V. Averyanova, R.S. Belkin, A.I. Vinberg, A.M. Zinin, A.K. Kavalieris, M.V. Kissin, Mitricheva V.S., Moiseeva T.F., Rossinskaya E.R., Saltevsky M.V., Samishchenko S.S., Snetkova V.A., Strogovicha M.S., Shikanova V.I., Yablokova N. .P. and other domestic scientists. Many foreign scientists and specialists in this field of knowledge also paid no less attention to this problem. Their research made a significant contribution to the development of the theoretical foundations and methodology for the use of detection dogs in the process of implementing methodological techniques for studying scent traces in connection with the detection and investigation of crimes. A significant contribution to the development of the olfactory direction of research on human scent traces, to the conduct of experimental work, the development, testing and improvement of the methodological base, and the organization of the implementation of the biosensory research method were also made by domestic scientists and practitioners in this area of ​​research: Sulimov K.T., Starovoitov V.I. ., Panfilov P.B., Salamatin A.V. and others.

Representatives of a variety of sciences and specialties studied the properties of human scent traces, the peculiarities of the dog’s sense of smell as a macrosmatic animal, and the patterns of perception of odor stimuli. Together, the research was carried out by specialists of various profiles: biologists, physiologists, ethologists, zoopsychologists and criminologists. Information about research in these areas for a wide range of readers is presented in the well-known book by R.H. Wright "The Science of Smells" 2.

In the development of forensic examination of human scent traces, the following sequence and continuity of ideas can be traced. The basic ideas of this area of ​​research, which contributed to its successful development, are presented in the works of many lawyers and natural scientists. Thus, G. Gross proposed using dogs in smell recognition; collect, preserve and use objects carrying odorous substances in investigations; use tightly sealed glass and tin jars for preserving and storing items that carry odorous substances 3. The concept of “canine (odorological) sampling,” used in forensic literature, is the name of a method developed in zoopsychology for selecting an object from a set according to a given sample 4 . It should be noted that Russian criminologists are little aware of the contribution of foreign researchers to the area under consideration, which is one of the pressing problems of using the examination of scent traces, therefore, unfortunately, it is underestimated when conducting research. The use of olfactory (i.e., obtained through the sense of smell) information in the detection and investigation of crimes is known mainly from the publications of arguing supporters and opponents of “forensic odology.”

The research of the developers of “forensic odorology” (mid-60s - 80s of the 20th century) is covered in the domestic forensic literature better than others. In 1964 At the Department of Criminalistics of the Higher School of the State Security Committee of the USSR, research began to find a way to identify a person by his scent traces. Developments carried out by the team of authors consisting of V.V. Bezrukova, A.I. Vinberga, M.G. Mayorov and R.M. Todorov 5 are associated with the invention of “odor sampling devices” (POS) for collecting portions of air with human scent traces for the purpose of using them in identifying criminals with the help of search dogs. The algorithm for such a procedure was called by the authors the method of “forensic odorology.” However, for a number of reasons, both theoretical and applied, the developers’ proposal to introduce this method into the work of law enforcement agencies was not accepted by either search or investigative practice.

An expert study of human scent traces seems unusual due to the inaccessible object of research: the molecular quantities of the mixture of odorous substances that make up such traces, and the means of identifying them that are unusual for criminologists - the sense of smell and conditioned reflexes of specialized detector dogs.

The dispute about the scientific validity of the use of detection dogs is caused by the use of the results of the study of human scent traces for procedural purposes. For example, V.I. Shikanov believed that “forensic odology” as a branch of criminology can gain the right to exist only when instrumental methods for studying scent traces are developed, and as long as a dog acts as such a “tool,” there is no “forensic odology” 6 .

One of the theorists of “forensic odology” R.S. Belkin also pointed out that the impossibility of instrumental verification of the results of canine sampling casts doubt on the reliability of human identification based on scent tracks. The same doubt R.S. Belkin spoke about the legality of formalizing “odorous identification” in the form of a forensic examination 7 . In his opinion, participants in criminal procedural evidence observing the biological detection procedure are deprived of the opportunity to fully assess the reliability of its result. And this makes it unlawful to use data obtained in this way in criminal procedural evidence. Therefore R.S. Belkin believed that in identification research it is necessary to combine biological detection and instrumental methods 8. There is also a point of view on this issue by A.F. Protopopov, which sounds more categorical. In his opinion, it is currently not possible to reliably identify a person by scent traces, and registration of a sample in the form of an examination report is not only doubtful, but also illegal 9 .

Let us note that such categorical judgments and rejection of animals as a tool in scientific research by criminologists during this period were a completely natural reaction to the lack of special knowledge on biodetection of qualitative and quantitative characteristics of human odor traces. However, such statements in our time can only indicate the lack of awareness of those speaking about the capabilities of modern technology of scientific biological experiments and special knowledge in this field of research. And yet we have to admit that some practical workers of the internal affairs bodies and the prosecutor's office still do not distinguish between an expert forensic study of a person's scent traces and an operational search activity - canine sampling using service-search dogs 10. The main difference between these actions is that the expert examination of scent marks, in accordance with Chapter 27 of the Code of Criminal Procedure of the Russian Federation, is an investigative action, its results are documented in a procedural document - an expert’s opinion 11, and a canine sample is documented in a special act on the use of a service dog 12.

Responding to opponents, supporters of A.I. Vinberg turned to the study of issues of procedural use of the results of the study of scent traces. The VNIISE of the USSR Ministry of Justice calculated the conditions for obtaining reliable data when using several dogs sequentially in an “odorological” (canine) sample 13 . Thus, the initial methodological basis for the criminal procedural use of olfactory information was created. Unfortunately, what is more often remembered is not these real achievements of the developers of “odorology”, but the unviable ideas of V.V. Bezrukov, associated with the collection of “molecules of odorous substances” from the air, within the framework of which the physical and chemical analysis of substances is considered, which has nothing to do with odors as sensations (Latin “odor”).

In general, the proposals of the founders of “odorology” remained unclaimed by practice due to weak organizational and methodological support for the procedure for studying traces of odorous substances and underestimation of the role of the specialists performing it. The question of creating special techniques for studying such traces was not raised at all at this stage of the development of the olfactory method.

Further development of this area of ​​research in the USSR and Russia is associated with the work of scientists and specialists of the All-Union Scientific Research Institute of the Ministry of Internal Affairs of the USSR and the Forensic Expert Center of the Ministry of Internal Affairs of Russia. With the participation of the All-Russian Research Institute of the Ministry of Internal Affairs of the USSR, the first laboratory in our country specialized in the study of human scent traces was opened in 1976 in the Jurmala City Department of Internal Affairs of the Latvian SSR. Here, the German identification research technique based on the use of preserved scent traces 14 was tested and adapted to local conditions. The study of the experience of German and Hungarian specialists (late 70s - early 80s), the legal basis prepared by domestic scientists for “forensic odology”, and their own research helped specialists from the All-Russian Scientific Research Institute of the Ministry of Internal Affairs of the USSR - ECC of the Ministry of Internal Affairs of Russia to develop the identification systems currently used 15 and a number of diagnostic 16 methods for studying human scent traces for forensic purposes.

The basis for the research of specialists from the All-Russian Research Institute of the Ministry of Internal Affairs of the USSR was not the “odorological” methods of domestic scientists, criticized by opponents, but the laboratory methods of German criminologists. In the early 80s. XX century, the comments of V.I. were analyzed. Shikanov and other opponents of “odorology”, solutions to the problems they raised were found.

An important contribution to the development of the methodology for olfactory research was made by V.A. Snetkov, who in 1983 published the article “Cynological Sampling”, which largely determined the direction of research by specialists from the All-Russian Research Institute of the Ministry of Internal Affairs of the USSR - ECC of the Ministry of Internal Affairs of Russia 17. This article discusses the issues of studying human scent traces using the sense of smell of dogs from the perspective of the theory of forensic identification, and formulates the requirements for research tools, including dogs and scientific and methodological support.

E.P. Zinkevich (Institute of Ecology and Animal Morphology of the USSR Academy of Sciences), K.T. Sulimov, V.I. Starovoytov (All-Russian Research Institute of the Ministry of Internal Affairs of the USSR) in 1984. A method has been developed for collecting substances that form odor traces by evaporating them from trace carriers and collecting them on cotton napkins and using thermal vacuum evaporation with cryogenic condensation. Specialists of the Expert Forensic Center of the Ministry of Internal Affairs have achieved success in studying the natural scientific foundations of the olfactory study of human scent traces: personal individuality, immutability, relative stability, the possibility of their collection and regular recognition using detector dogs 18.

In the nineties of the 20th century, techniques for identifying certain diagnostic characteristics in human scent traces were developed, 19 which significantly expanded the research capabilities of criminologists. The conducted studies and statistical calculations characterize the reliability of the results obtained using the olfactory method of studying human odor traces as comparable to the reliability of the results of DNA analysis, because the probability of error with a categorical positive conclusion about the presence of odor traces of a specific person on the object under study using at least three animals in the study does not exceed 1.02 · 10 –8, with the use of four animals – 2 · 10 –11.

Currently, the developments of specialists from the Expert Forensic Center of the Ministry of Internal Affairs of Russia, based on experimental research and expert practice, form the ideas of domestic criminologists on the use of human scent traces in operational and investigative work.

The study of human scent traces using their own methodological developments has been carried out by specialists from the ECC of the Ministry of Internal Affairs of Russia since 1983, its results have been used in courts for many years along with other sources of evidence. Expert studies of human scent traces using the methods of the ECC of the Ministry of Internal Affairs of Russia are carried out in a number of other expert and forensic units of the internal affairs bodies of Russia - in the Ministry of Internal Affairs of the Republic of Tatarstan (since 1998), the Ministry of Internal Affairs of the Republic of Khakassia (since 2006), the Central Internal Affairs Directorate of the Altai Territory (since 2000) , Main Department of Internal Affairs of Volgograd (since 1997), Saratov (since 2004), Department of Internal Affairs of Kirov (since 2004) and Yaroslavl (since 2006) regions, as well as the Ministry of Internal Affairs of the Republic of Belarus (since 1996).

The method of olfactory research is used in a number of European countries (Belgium, Hungary, Germany, Holland, Denmark, the Netherlands, Poland, Slovenia, the Czech Republic, France, etc.). The methodological requirements for the study of scent traces in the ECC of the Ministry of Internal Affairs of Russia seem to be more stringent than those used by Hungarian, Dutch and Polish and other foreign criminologists. It is important that the methods for studying odor traces are based on the methodology of a scientific experiment, which consists in the fact that the laboratory experiment must be controlled and reproducible.

In 1993-1996. A laboratory for olfactory research has been organized within the structure of the biological department of the State Expert and Forensic Center of the Ministry of Internal Affairs of the Republic of Belarus, where 350-400 expert studies of human scent traces are carried out annually. For the period from 1996 to 2007, based on materials from the internal affairs bodies, the prosecutor's office, the courts and the State Security Committee of the Republic of Belarus, the department for the study of human scent traces carried out 2,695 examinations and studies, many of the results of which were used in judicial consideration of criminal cases and were significant evidence to incriminate criminals.

It should be noted that the number of studies performed is growing from year to year. This trend continues this year - in the first quarter of 2008, 180 examinations and studies were completed.

The bank of scent traces from unsolved crime scenes is being actively replenished. By the end of 2002, there were more than 1,200 traces in the jar.

If we analyze the distribution of materials completed over all years of the department’s operation by crime, the following picture emerges (see diagram 1).

Currently, the scientific validity and reliability of the results of studies of human scent traces is recognized. A regulatory framework has been created to use the capabilities of scent trace research, including the permissibility of conducting an examination of scent traces and using its results as material evidence. Order of the Ministry of Internal Affairs No. 511 of June 29, 2005 “Issues of organizing forensic examinations in the forensic units of the Internal Affairs Bodies of the Russian Federation” stipulates that the examination of human odor traces is one of the types of research carried out within the framework of the biological examination of human tissues and secretions. In orders of the Ministry of Internal Affairs No. 1171 of December 31, 2005 “On approval of the manual on organizing the activities of canine units of the Internal Affairs Bodies of the Russian Federation” and No. 816 of October 20, 1999. “On measures for the further development of the canine service in the system of the Ministry of Internal Affairs of Russia” regulates the use of detector dogs in the study of scent marks.

The continuing increase in crime requires the adoption of adequate measures by law enforcement agencies. Such measures include the improvement of technical and forensic tools used to identify, record, seize, preserve and study traces of a crime, to solve, investigate and prevent crimes. The main work to identify, record and remove traces of a crime is carried out during the inspection of the crime scene. It is at this stage of the investigation that the investigator faces a number of tasks, among which the main place is the detection and seizure of traces of a crime, which in the future can become material evidence in a criminal case.

Odor traces are material micro-formations of an odorous substance, limited in space by a threshold concentration for them, which remain at the scene of an incident as a result of the interaction of the source of the smell with environmental objects and individualize the subject who left this smell. On the one hand, sources of odor are physical bodies or living organisms that produce odor, and on the other, their parts are broken off nails, hair, pieces of epidermis, blood, hair, etc. An independent group consists of objects that have absorbed the smell of a person - things worn person (gloves, clothes, hats, etc.); instruments for committing a crime; objects that a person touched - a cane, a pack of cigarettes, a lighter, a wallet, etc.

In the village of Malta, Usolsky district, the body of a man (as it turned out later, citizen Aikin V.) with a severed head was found. A criminal case was opened into the murder. A certain Togolev P. was suspected of the murder; during a search of his house, blood stains were found on the floor and on the threshold, as well as a bag with the same stains. In the basement of the house, potatoes were found with brown spots that looked like blood and hair. All traces identified at the scene of the incident were appropriately removed and sent for odorological examination. The study established that in the stains taken from the floor, threshold, potatoes and bag, there is an individual smell of Aikin V. In the seized hair, the smell of Aikin V was also detected.

Odor traces or objects with such odor formations fully meet the requirements for material evidence. So, according to Art. 83 of the Code of Criminal Procedure of the RSFSR - material evidence is objects that served as instruments of a crime, or retained traces of a crime, as well as all other objects that can serve as a means of detecting a crime, establishing the factual circumstances of the case, identifying the perpetrators, or refuting charges or mitigating responsibility. The scent traces detected at the scene of the incident, as well as objects with such traces, fully comply with the presented wording of the article of the Code of Criminal Procedure and make it possible to resolve the tasks assigned to them by the criminal procedure law. Taking into account the requirements imposed on them, odor samples and odor-carrying objects seized from the scene of the incident possess the entire complex of necessary characteristics that characterize the object of odorological research as material evidence:

1. Scent marks left by the criminal and (or) other involved persons at the scene of the incident have a causal relationship with the event under investigation.

2. The odorous substances that make up the samples taken are material in nature and obey physical and chemical laws. They can be collected, stored, divided, and researched.

3. Smells from the traces of a particular person have individual characteristics that qualitatively distinguish him from the odors of other people.

4. Odor traces and samples collected from them can help establish the presence or absence of elements of a crime; allow you to determine, and in some cases exclude, the subject’s involvement in the incident; contribute to identifying the place, method and other circumstances of the crime.

5. Odor traces that individualize a person have functional characteristics that can be identified and studied in laboratory conditions. Specialists determine the suitability and sufficiency of the samples obtained, establish group classification characteristics, the presence of odorous backgrounds, household and industrial odor interference, and identify components that individualize the desired object.

6. By order of the investigator or a court ruling, seized samples or odor-carrying objects may be added to the case as material evidence associated, presumably, with the sought fact.

As stated above, the discovery of such material evidence takes place mainly during investigative (judicial) inspections of the scene of the incident in the manner provided for in Art. 178, 179 Code of Criminal Procedure of the RSFSR. But if special research is required to identify a material object, then such a problem can be solved by expert means, in laboratory conditions. Thus, human odor is obtained from traces of blood directly in an odorological laboratory. At the scene of the incident, traces of blood are removed according to the general rules established for objects of forensic medical examination.

Since scent traces relate to micro-objects, the work on their detection, recording and removal is organized and carried out in exactly the same way as in relation to other micro-objects, in relation to which the investigator cannot come to a categorical conclusion about the possibility of their formation and location in a certain place . It must be remembered that traces of odor are subject to faster disappearance than other micro-objects. This circumstance predetermines the specifics of working with them at the scene of an incident, and also requires knowledge of the technique for collecting them by all members of the investigative team.

Odor traces must be removed immediately at the very beginning of the inspection, before the participants introduce foreign odors to the scene. The investigator must remember that he needs to work at the scene of the incident in collaboration with other specialists based on the characteristics of the crime, the presence and preservation of trace information. Scent information should initially be used to use a search dog “in hot pursuit,” and only after that, if possible and appropriate, scent traces are removed from objects and traces and stored for subsequent laboratory research. However, paying attention to scent trails does not mean abandoning the use of trails of other species. In any case, the protocol for examining the scene of the incident must record the techniques and methods for removing traces, means for working with scent traces, and objects that bear traces. The search, fixation and removal of odor traces invisible at the scene of an incident are carried out by analogy with the same actions that are used in relation to, for example, single textile fibers, the possible locations of which are established by the probabilistic method, through a logical understanding of the situation, using the method of induction or deduction. Only instead of treating (according to one of the existing methods) with adhesive film the areas where the criminal is supposed to come into contact with objects, cotton napkins (baizes) are applied to these places and pressed for a certain time to collect odor samples.

Seized samples and objects in the presence of witnesses must be properly sealed and included in the criminal case as material evidence. We share the opinion of Professor D. A. Turchin, who points out in particular that if the search for microtraces (including odor traces) is carried out using a probabilistic method, then witnesses, obviously, should only certify the fact of seizure for subsequent examination of the object, acting as the bearer of these microtraces.

When deciding on the removal of odor samples, it is necessary to take into account the state of the environment and assess the possible period of preservation of odor traces on certain objects. The safety of odor traces and their suitability for analysis are significantly influenced by time, atmospheric factors, physiological state and human habits.

The following must also be taken into account:

§ an increase in the time of contact of a person with a trace-carrying object contributes to a greater accumulation of odorant substances in traces that characterize the individual;

§ the insecurity of scent traces left by humans leads to their volatilization naturally into the environment;

§ increased temperature, humidity, air movement do not contribute to the preservation of odor traces; they last longer on dry, cold objects, in the absence of wind;

§ odors are retained better on porous, rough surfaces (paper, wood, hair, fabric). Worse - on smooth, dense (glass, metal, plastics, varnished and polished surfaces);

§ the level of hygienic culture, physiological characteristics and mental state of a person (sweating, physical activity, anxiety) during the leaving of traces significantly change their quantitative and qualitative characteristics, affect the period of preservation of the left odor traces;

§ odor traces formed during short-term (minute) contact of a person with objects persist in natural conditions for only a few hours.

Tracer objects covered with mold, the skin of a corpse, its hair and blood that have undergone putrefactive changes are not suitable for use as a source of odor. At the same time, pollination with pepper, tobacco and other respiratory tract irritants, as well as contamination with fuels and lubricants (fuels and lubricants), medicinal substances, perfumes, food and other additives, does not interfere with the laboratory study of human scent traces.

According to experts from the ECC of the Ministry of Internal Affairs of the Russian Federation, the duration of preservation of human odor traces on some carrier objects looks like this:

1. Traces of blood (including dried stains), hair - from several months to several years (at least 16).

2. Personal items (comb, notebook, etc.) - from several days to several months.

3. Worn (containing sweat and its evaporation) items of clothing, shoes - from several days to several months.

4. Objects that were in contact with the human body for at least 30 minutes (ropes, weapon handles, bags, seats, etc.) - up to three days.

5. Objects that were in minute contact with the human body - up to one or two hours.

6. Traces on the snow and soil - from several hours to a day.

In determining the location of scent traces at the scene of an incident, a probabilistic technique is used, which consists in the participants’ logical understanding of the situation, the sequence and mechanism of the crime, and in identifying objects with which the criminal could have been in contact for a certain time. In this case, the following circumstances must be taken into account:

a) time, place and method of committing the crime;

b) the specifics of odor source objects;

c) the alleged participants, the nature of their participation, their location at the time of the commission of the crime; the possibility of obtaining the necessary odor samples and other factors.

When working with scent marks, you must follow a number of rules:

a) all technical and forensic means used for seizure and preservation must be sterile. Such means are:

§ baize or flannel napkins;

§ hygiene gloves;

§ aluminum foil, never used;

§ glass jars with a capacity of 0.2-0.75 liters;

§ medical syringe; tweezers and some other items;

b) before removing an odor-carrying object, it should be inspected for traces of papillary patterns and foreign micro- and macroparticles - traces of overlap;

c) in order not to possibly damage the traces of papillary patterns on the discovered object, you must first think about how the criminal could have held it, and then take it accordingly;

d) when examining small objects, you should use tweezers, and examine large objects only with rubber gloves. All small items are removed for subsequent laboratory testing;

e) after inspection, the odor-carrying object must be preserved, that is, placed in an appropriate hermetically sealed container.

If an object with an odor trace cannot be removed in kind (shoe marks on the floor, asphalt, snow), as well as when working with odor traces at the scene of an incident, the following methods for removing odor traces are used, such as:

§ suction (sampling) of odor molecules with a medical syringe;

§ collection of odor molecules directly from the container;

§ adsorption of the odor trace on artificial media (bike).

The adsorption method is today the main method of collecting odor samples from the scene of an incident and from specific individuals being tested for involvement in a crime. It consists of applying an adsorbent (scraps of flannel, flannel, gauze napkins) measuring approximately 10x10 cm to an odor-carrying object, which perceives the smell. The accumulation of odorous substances by the adsorbent occurs during the entire period of inspection of the crime scene. It must be remembered that the minimum contact time of the adsorbent with the odor-carrying object should not be less than one hour. Increasing the contact time contributes to better collection of odor samples.

Before removing the odor trace, the odor-carrying object is slightly moistened with water from a spray bottle. After this, an adsorbent is applied, covered with two or three layers of foil and carefully crimped with tape, which ensures fairly tight contact of the fabric with the object. The opinion of the authors who propose covering the adsorbent and foil with plastic film to improve the process of diffusion of odor molecules and their adsorption seems rational.

In addition, it is necessary to remove the so-called control odor of the object itself from which the odor trace was adsorbed. To do this, a piece of flannel is placed on an area of ​​the object that is free from human odor, covered with two or three layers of foil, crimped tightly and left for at least one hour.

Investigative practice confirms that at the scene of an incident a criminal often loses gloves, mittens, a hat, a handkerchief and other things. These items contain a large amount of odor substance, which makes it possible to preserve several samples of odor from the same source in parallel. In Makhachkala, Gaziev was killed in a robbery in his apartment. Leather gloves were found at the scene, apparently left behind by the perpetrator. Inside these gloves, a second pair of rubber gloves was found. When re-inspecting the scene of the incident, among the victim’s belongings, the alleged criminal’s personal belongings were found. These items and gloves were sent for an odorological examination. The experts gave a categorical conclusion about the identity of the odor traces from the objects of the comparative study. After identifying the suspect, a new odorological examination was carried out, comparing the suspect's odor samples with traces of the odor of gloves and things. Experts have re-established their identity. Later, when pronouncing a guilty verdict, the court named this conclusion as evidence of the defendant’s guilt.

Odor traces left on small-sized objects can be removed directly from the objects. In Tver, counterfeit prescriptions for narcotic drugs were found in several pharmacies in the Central District. Following the necessary rules, prescriptions were collected from pharmacies and placed in hermetically sealed jars. After some time, two people were detained on suspicion of forging prescriptions and obtaining drugs. Experimental odor samples were taken from them. An odorological examination concluded that traces of odor on the prescriptions were left by them.

All odor samples seized at the scene are placed in glass jars with tightly sealed lids (each sample separately). Labels and tags are placed on the jars indicating the date; place and time during which scent traces were collected; during what investigative action and for what case were they seized; from which object were the odor samples collected (trace carrier material); special conditions at the site of seizure (strong odors, animal odors, wind force, temperature, precipitation). All this data must be certified by the signatures of the persons making the seizure and witnesses.

Scent traces taken from the scene of an incident can be used both in the process of conducting verification activities at the stage of initiating a criminal case, and during the preliminary investigation.

It is often necessary to take scent samples from a person being tested for involvement in a crime. In compliance with the requirements of Art. Art. 186, 141 of the Code of Criminal Procedure of the RSFSR, odor samples for comparison can be obtained from the suspect or accused, and, if necessary, from a witness or victim. The best and purest source of a subject's individual scent is his blood. If this is not possible, the subject's underwear or sweat samples may be used as sources of individual odor. The proven methodology for selecting comparative samples takes into account the requirements for protecting the honor, dignity and health of the person from whom odorous samples are taken on cotton napkins (baika). There are also certain rules for smell selection:

1. The investigator must make decisions on the removal of odor samples from a specific person being inspected for comparative research;

2. The collection of samples of individual odor and odor traces from the scene of an incident should be carried out by different people in order to avoid repetition of components in odor samples. To avoid impurities getting into the smell samples, it is better to carry out the sampling with rubber gloves and also use tweezers. You can also give the person from whom the odor samples are taken to remove flaps of flannel from the jar (or foil) and place them separately, unfolded, on the body. These flaps should be removed from the body no earlier than after 30 minutes of contact;

3. Sources of individual odor can be: sweat secretions collected on a bike, or a person’s worn clothing;

4. Selection of a reference odor trace left on an object similar in material to the trace carrier identified at the scene of the incident. The time of contact between a person and an object when receiving a reference trace is determined based on the version being checked;

5. Preservation of individual odor samples is carried out according to the rules for collecting odor samples at the scene of an incident in glass, tightly sealed jars with a capacity of 0.5-0.7 liters;

6. Witnesses are invited to participate in the investigative action to select odor samples for comparative research. Their presence ensures the authenticity of the origin of the samples received and the correct display of the progress and results of the investigative action in the protocol.

Samples for comparative research are taken from areas of the skin that do not have obvious contaminants (including odors of perfumes, medicines, fuels and lubricants, food products, odors of strangers).

In cases where odor sampling is carried out in a room, it is necessary to obtain the background odor of the room itself.

The suitability of comparative samples characterizing the subject being tested for involvement in the incident is determined by the following reliability criteria:

§ reliability of origin from the person being verified;

§ sufficient concentration;

§ cleanliness - the absence of foreign odor inclusions or the overwhelming predominance of odor substances from the body of the subject being tested.

Scent samples with standards from the persons being tested are also packaged and provided with labels (tags), which indicate: the name of the person from whom the smell sample was taken, occupation, age of the person being tested, from which part of the body the sample was taken, the time of contact of the piece of flannel with the body, as well as the presence or absence of characteristic odors in the air of the room where the samples were taken. If reference odor samples are not provided for examination, the decision must indicate the circumstances precluding the possibility of obtaining them.

Odor samples taken from the persons being checked allow us to determine or exclude the latter’s involvement in the incident. In this case, the following tasks are solved:

§ establishing the individual scent of the same person in scent traces taken from different places;

§ establishing that the items left at the scene of the incident belonged to the criminal;

§ establishing that the stolen items belonged to the victim;

§ obtaining additional information during a comprehensive examination of material evidence.

Odor traces and samples of individual odors seized from the scene of the incident, tested for the involvement of persons in the event, are sent to the laboratory of forensic odorology for an odorological examination. The person conducting the inquiry, the investigator or the judge, when issuing an appropriate resolution on the appointment of an odorological examination, indicates in it:

1) by whom and when this examination was appointed;

2) a brief plot of the criminal case;

3) which body (organization, institution) is entrusted with conducting the odorological study;

4) issues that require special knowledge to resolve;

5) 5) items (samples) submitted for research. All items and samples must be presented in sealed form, intact and intact, and also provided with explanatory notes and certified by the signatures of witnesses. The resolution is signed by the person who appointed the examination.

The main task facing the odorological examination is to establish the identity of a certain person by the smell he left and determine whether the smells were left by the same or different people on one or more objects (subjects) submitted for research.

The obtained results of the study of seized scent traces and odor samples are assessed in conjunction with other evidence collected in the criminal case.

Koisin A. A.
Siberian Legal Bulletin. - 2001. - No. 4

Literature:

Inspection of the scene of the incident: A practical guide / Ed. A.I. Dworkin. M.: Yurist, 2001. P.14.

Odor traces at the scene of the incident (memo for the participant in the inspection of the scene of the incident). - M.: ECC of the Ministry of Internal Affairs of the Russian Federation, 1995.

Turchin D.A. Microtraces - new in criminology / Problems of the Soviet state and law. Irkutsk, 1974. Issue 7. P.104-109.

Starovoitov V.I., Sulimov K.T., Grishchenko V.V. Scent traces of participants in the incident: detection, collection, organization of investigation. Guidelines. M.: ECC of the Ministry of Internal Affairs of the Russian Federation, 1993. P.7.

Fedorov G.V. Odorology: scent traces in forensics. Mn.: Amalthea, 2000. P. 75.

Starovoitov V.I. and others. Decree op. S. 8.

Saltevsky M.V. Forensic odology. Working with scent marks. K.: KVSh Ministry of Internal Affairs of the USSR, 1976. P.27-28.

Razumov E.A., Molibova N.P. Traces of smell // Inspection of the crime scene. Methodology and tactics. Kyiv: RIO Ministry of Internal Affairs of Ukraine, 1994. P.545.

Fedorov G.V. Odorology: scent traces in forensics. Mn.: Amalthea, 2000. P.87.

Forensic odology as a branch of forensic technology represents a system of scientific techniques and technical means for detecting, analyzing, seizing and storing odor traces for their subsequent use during the preliminary investigation in order to identify a specific person and his objects, belongings, documents and other objects by individual smell.

Humans excrete many dozens of chemical compounds as waste products.. These compounds are formed in the body during the metabolic process and are released into the environment with exhaled air, urine, and secretions of the sweat and sebaceous glands. Some of them carry information about a person’s gender, physiological, functional and emotional state. In addition to the permanent characteristics of an individual, they can also reflect temporary (random) ones, such as the place of recent stay, spicy food eaten, etc. Using appropriate techniques, it is possible to detect and remove, preserve and preserve human odor molecules suitable for use for a long time (several years).

Depending on the methods of analysis and registration of odors in forensic odology, it is distinguished between canine and instrumental components.

IN canine odorology The olfactory organ of a service dog acts as an analyzer of odorous substances.

IN instrumental odorology (olfactronics) physical and chemical devices are used as analyzers that are capable of identifying a spectrum of odorous substances, recording it in the form of an olfactogram and detecting with high sensitivity individual components of odorous human secretions.

The significance of odor traces for solving forensic problems is due to the fact that they are formed almost continuously and as long as the source of the odor exists.

Based on the nature of formation, odorological traces are divided into:

• Smells- associated with the evaporation of molecules of odorous substances located in a confined space and quickly dissipating outside it.
• Sources of odor- solid and liquid objects from the surface of which odor molecules continuously evaporate, affecting the olfactory receptors

The smell left by a person is always mixed with the so-called background smells, emitted by damaged soil cover, crushed small insects, plants, etc. It has been experimentally proven that background odors, as well as the odors of different people, do not mix with each other and do not result in a new smell.

Using modern methods of analysis (gas and paper chromatography, mass spectrometry, etc.), more than 400 chemical compounds belonging to organic and inorganic substances were isolated and identified by smell.

Study of the conditions for the formation of odor traces constitutes one of the areas of research in forensic odology. These traces are divided into three groups:

• Fresh - discovered within one hour from the moment they were left;
• Normal are traces detected within a period of up to three hours, and old ones three hours after formation.
• Old - the practice of forensic odorology shows that in closed, unventilated rooms, odor traces remain on highly absorbent media for up to two years.

Experiments have shown that dogs can easily distinguish people and even members of the same family by smell, unless they are identical twins. The individuality of smell is probably genetically determined, since only such twins have the same genetic constitution. It has been established that the individual component of a person’s odor does not depend on his diet, clothing or home environment.

Objects that carry human odor are sweat, blood (including in dry spots), hair (retain a person’s individual smell for decades); personal belongings (worn items of clothing, shoes retain an individual odor from several days to several months); various objects (means of committing a crime, weapons, etc., which have been in contact with a person for at least 30 minutes, retain their individual smell for up to two days).

On things and objects buried in the ground or snow, scent traces are present for up to several months. Thus, on accounting journals buried in a flowerbed in a metal box, traces of odors could be detected even after 7 months. Odorological traces are well preserved in the cold, in the shade, indoors, on porous, rough surfaces; worse in the wind, on heated and smooth objects.

To correctly determine the likely locations of scent traces and odor-carrying objects, it is necessary to model the behavior of criminals at the scene of an incident, paying attention to the places where they spent a long time.

When analyzing scent traces, the following tasks are solved:

• detection of participants in the crime;
• identification of the individual odor of the same person in scent traces taken from different crime scenes;
• establishing the belonging of the criminal to the items found at the scene of the incident;
• establishing the belonging of objects seized from the criminal or other persons to the victim;
• determination of the origin of odor from specific individuals during a comprehensive examination of material evidence.

Odor traces are formed as a result of direct contact of various objects with the human body from a source that continuously generates odorous substances. These substances can be taken from the body, clothing, belongings of an individual, his documents, from volumetric and superficial traces of feet and hands, from obstacles that he overcame or damaged, from the body and clothing of the victim, objects and instruments of crime, from the air of premises where the person of interest investigation the subject was permanently or temporarily present, etc. Odor is also carried by human excretions (urine, semen, etc.), as well as hair and skin flakes separated from the body.

When carrying out urgent investigative actions, work with scent traces is carried out according to general rules, but taking into account the features characteristic of these traces:

• creating conditions that ensure maximum preservation of odor traces;
• limiting the number of participants in the inspection of the crime scene to only necessary persons;
• compliance with the rules of behavior and movement that prevent damage to traces or their contamination with foreign odorous substances (inspection participants must stay within the designated area, move only with the permission of the inspection leader, do not smoke or create drafts);
• strict order of search and removal of scent traces.

When removing scent traces, a syringe (veterinary, medical) with a nozzle on the tip, glass bottles with ground-in stoppers, sterile medical gauze wipes and sterile medical cotton wool included in the investigation suitcase are used.

If the criminal left personal belongings and objects at the scene of the incident, then using tweezers or hands in rubber gloves, each object is placed in a separate new plastic bag, which is hermetically sealed. For better sealing, double polyethylene bags are used, in which scents can be stored for months without losing their individual qualities.

Odor samples are taken using cotton or gauze swabs. To do this, take a sterile swab with tweezers, rub it with light pressure over the surface of the odor carrier and place it in a sealed dark glass container. Thus, odorous substances are taken from the suspect’s clothes, his personal belongings and shoe prints.

Odor samples can also be obtained using the adsorption method., which refers to the absorption of a substance from a solution or gas by the surface layer of the sorbent. To do this, odorous substances are sucked out from the scent trail with a syringe and pumped into a container. At the bottom of the container there is a sorbent (sterile cotton or gauze swab), after which it is hermetically sealed.

To better extract the smell from the trail, aluminum foil and plastic film are placed on top of the sorbent, pressing them with a weight. If the trace is located on the vertical surface of the carrier object, then the sorbent, foil and film are reinforced with adhesive tape. When you need to collect odor from a spherical or shaped surface (for example, a door handle, car control levers, etc.), it is wrapped in a piece of sorbent. When removing odor from voluminous or superficial traces of feet or hands, a box is placed on top of the sorbent on the area of ​​the carrier object. A “microclimate” is created under it, enhancing the evaporation of the odorous substance.

Odor samples can be taken using polyethylene flasks, syringes and other suction devices (by creating a vacuum) both from traces of a person, objects, things, weapons of crime, clothing, etc., and from the air of enclosed spaces. The samples taken are pumped into hermetically sealed containers for storage and subsequent use in identifying criminals.

Service dogs quite clearly “recognize” people by smell samples from rooms in which they were 10-15 minutes, as well as by smells taken from small objects (matches, buttons, nails, etc.). If there are odors of other people in the room, this does not have a significant impact on the quality of the sample.

Odorous substances remain in indoor air for 2-3 days, and even short-term ventilation does not eliminate them. For a reliable odorological sample, a few tens of cubic millimeters of air with molecules of odorous substances taken from a person or his trace are sufficient.

For selection and long-term storage with the possibility of repeated presentation of the smell, a special device is used, which is based on the sorption principle. Activated carbon is recognized as the optimal sorbent, retaining the odor sample for up to two years and providing the possibility of its repeated (5-8 times) use.

The Hornet device is more compact, consisting of a two-cylinder hand pump and capsules with activated carbon. The carbon filling the tubes can be recovered and reused after use. Regeneration is carried out by calcination for two hours at temperatures up to 200C.

Human odorous substances on footprints, shoes, crime weapons and the scene of an incident in an open area remain for 20 hours, and on personal belongings and objects for up to several days.

The shelf life of odor traces depends on the volume and degree of ventilation of the room, as well as on the odor-perceiving properties of the location of the carrier objects. So, on a cotton stocking buried in the snow to a depth of about two meters, the smell lasted for more than 40 days, and on a filing cabinet buried in the ground in a cardboard case for more than 6 months. Based on these tracks, with the help of a sniffer dog, the owners of these items were identified.

Before the development of canine odorology, it was believed that it was impossible to use service dogs on tracks treated with sharp-smelling and harmfully active substances, since they irritate the dog’s nasal mucosa and dampen the main smell. However, the human odor is formed by highly volatile sweat and fat components, while gasoline, turpentine, acetone, alcohol, cologne and other odorous substances consist of highly volatile components. They evaporate much faster than sweat marks from hands and feet. Due to this difference, it becomes possible to use for sampling traces that were deliberately treated by the criminal with substances that have a harmful effect on the olfactory organs of dogs. You just need to wait a certain time until the pungent-smelling substances evaporate, take a sample of the criminal’s scent traces and preserve it for later use.

Human biological secretions (saliva, urine, blood, sperm, etc.) contain individual odorous substances. These secretions, as well as hair from various parts of the body and cut nails, are effective for picking out things and objects with the help of a service dog.

Methods for removing, packaging and storing human biological secretions are generally the same as for removing odor samples or carrier objects. When biological secretions are present on seized objects and things, they should be placed in sealed containers. If the discharge is on the ground, it is advisable to remove it along with part of the soil and pack it in a closed glass container. When biological secretions cannot be removed together with the carrier object, samples of the odorous substances that form them should be taken on gauze swabs, as well as several odor samples with a syringe and pumped into hermetically sealed containers. After the seizure and packaging of biological secretions, it is recommended that bottles, jars and plastic bags be labeled with the number of the criminal case, location, time of seizure, etc. The containers are sealed.

Odors taken and preserved in a timely manner can be sent by mail to make samples of the suspect’s belongings and objects. It is best to send items of clothing (shirts, handkerchiefs, hats, shoes, collar collars, etc.), since they contain quite a lot of odorous substances. When several suspects living in different places are involved in a case, the same thing found at the scene can be sequentially transported for odorological sampling. After each sample, it must be immediately sealed.

One of the main tasks of instrumental odorology (olfactronics) is development of methods and equipment for recording the spectrum of odorous substances, determining odor and documenting it in a form that will be amenable to mathematical processing, as well as recording individual components of human odor secretions.

A laboratory setup is currently being developed to prepare an odor sample for chromatographic analysis. It uses the aerosol-cryogenic method of concentrating volatile components to identify a person by smell.

The selection of samples for comparative odor research is documented in a protocol for the collection of samples of odorous substances.

When ordering an odorant examination, the following questions may be asked:

• Is the odor of a person detected in the odorological sample collected from the object (subject)? If so, does it come from the person being verified?
• did a man or a woman leave scent marks?
• Does the blood, hair, or sweat found at the scene come from the person being tested?
• Judging by the smell, were the footprints (hands) found at the scene left by the person being checked?
• Is there an individual smell of the person being checked on the seized item (clothing, shoes, weapons, comb, cigarette butt, etc.)?

Depending on the source of the odor and the qualitative and quantitative characteristics of the trace it leaves, objects of odorological origin are examined using technical means or a biodetector.

In instrumental odology, physicochemical devices are used as an analyzer, capable of identifying a spectrum of odorous substances, recording it in the form of an alphagram and recognizing with high sensitivity the individual components included in the odor traces.

Instrumental methods for odorological purposes are used only to study single-odor traces.

The situation is somewhat different when it comes to using the olfactory abilities of a specially trained dog to identify a person by his individual scent trail, as well as with the use of identification results in the process of proving the circumstances of the crime under investigation.

The basis for the use of service dogs in odorological identification is their significant superiority over currently existing devices. A biological detector differs from a technical one in that, on the one hand, it has integrative perception, i.e., it reacts to a synthesized complex of odors (individual odor bouquet) emanating from metabolites, as if it were the smell of a new substance, and on the other hand, it has the property of selectivity, the ability select the desired scent from a diffuse mixture of different scents.

It is known that the smell emanating from human traces left on the ground is always mixed with so-called background odors: damaged soil cover, crushed small insects, plants, etc. However, this does not prevent the dog from perceiving the smell of a person and searching for it.

There are results of studies of the influence on the formation of human odor of medications taken for a long time by people suffering from various diseases. Odor samples were obtained before, during and after drug administration. When comparing scent samples taken from these individuals, in no case was there any deviation in the signal reaction of the differentiator dog to the smell of the same person. There were also no cases of positive sampling of different individuals taking the same medications.

A study of the nature of human odor has shown that its individual odor bouquet is found only in metabolites. Chemical analysis of the metabolite leads to the destruction of the aroma bouquet. An attempt to synthesize it does not contribute to the restoration of individual odor. The mystery of the nature of human smell has not yet been solved. Therefore, its identification using instruments remains inaccessible.

Based on the foregoing, we can conclude that the most effective means of identifying human odor today is still the sense of smell of animals.

The use of a natural analyzer, which is the dog’s sense of smell, in odorological studies is explained by the following: the dog in its life activity is guided mainly by odor information; olfactory processes are based on reflexes; the sensations that arise during exposure to the smell are stored in the dog’s memory for quite a long time; recognition processes proceed quickly.

The guarantee of successful application of the odorological identification method lies in obtaining clear, reproducible and adequate signals from the dog. For this, three systems are used to control the correct behavior of the biodetector.

Statistical control is carried out due to repeated recognition of the desired sample when its location among 10 known objects changes. The possibility of error in such control is defined as 0.1", where n is the number of uses of the dog, usually equal to three for each dog.

The individual abilities of detector dogs are taken into account. To ensure reliable results, it is advisable to use three dogs.

The principle of monitoring results using control samples (standards), adopted in instrumental and chemical analysis, is used. Each time a dog is used, its functional state and disposition to search for a given odor are considered positive if it finds a specially prepared duplicate - an object with the same odor. In addition, a special test identifies odor interference to which biodetectors can respond. To do this, the dog is allowed to smell the scent of a neutral person who is not involved in the event being studied. The object from the scene of the incident and a duplicate of the neutral sample are placed in a comparative row among the auxiliary objects, along which each dog is walked. Correct recognition of a duplicate sample indicates normal operation of the biodetector. Increased interest in the odors being tested indicates detection of an interference.

To successfully carry out odorological identification, a number of rules must be observed:

the collection of odor samples at the scene of the incident and from the person being tested is carried out by different people;

the samples being compared are freed from foreign odors (as far as possible);

Contacts of the dog with the person being checked or his belongings are excluded; the objects being tested are placed at an equal distance from each other around the circumference;

At the testing site, the presence of the odor specified for the search (reference sample) must be present;

Several dogs are used during the research process; opportunities are created equal for conclusions of both an affirmative and negative nature in relation to the person being inspected;

the specialist conducting the research should not know about the location of the desired object in the comparative row in order to avoid uncontrolled influence on the signal behavior of the detector dog.

Tactical features of the production of odorological identification are that the study is recommended to be carried out 24 hours after the removal of the trace or odor sample on the adsorbent so that the latter reaches the temperature of the room where the sample will be taken.

The sampling is carried out in three stages: preparatory, comparative and evaluation. During the preparatory stage, all factors that may affect the reliability of the sample should be studied, and measures should be taken to take into account or eliminate their negative impact on the course of the latter, its results and their assessment. The sampling objects, the technical support of the event (characteristics of the premises, the state of readiness of the animal for sampling, etc.) are studied, the availability of the necessary participants is clarified, and in accordance with the data obtained during the study, the objects, premises, animal (or animals) are prepared for sampling, instructions are given participants in the investigative action. As for the sample objects (traces), their nature, origin, the period of time that has elapsed from the moment they were left at the scene of the incident, the methods and means of removal, recording, and storage conditions are analyzed. In accordance with the results of these activities, neutral objects are selected that will be used for sampling.

At the stage of comparative research, all means and methods of odorological identification necessary for participants in the investigative action to obtain an objective idea of ​​the coincidence or difference of sample objects must be applied. This is carried out on the basis of data obtained at the preparatory stage, when the dog is working at the time of repeated sampling, when the order of sampling or the position of identification objects is changed, as well as when sampling objects in the same population by different animals.

During the assessment stage, data about the presented objects, the conditions for their presentation, the behavior of the dog are analyzed, i.e. all the data obtained during preparation and comparison in a complex, from which a conclusion is drawn about the presence or absence of identity. At the same time, the specialist explains the dog’s behavior and draws a conclusion.

The peculiarities of the odorological identification technique are that the study is carried out in a specially adapted laboratory room with the maximum possible elimination of extraneous irritants and optimal conditions for detection dogs (temperature 20 ° C, air humidity 60-80%). Eight to ten glass jars with test and auxiliary samples prepared for analysis (a comparative series of odorological objects) are placed on numbered points on the floor of the room at a distance of 1 m from one another. Odor samples obtained from human contact marks left on model objects by persons not involved in the incident are auxiliary. Containers with objects are placed in metal racks that cover explanatory inscriptions on the jars (to exclude unintentional hints to biodetectors from the specialist managing them).

The study uses specially trained detector dogs, having previously checked their functional state (detection ability) in searching for auxiliary odor samples according to a given pattern, recording the signaling behavior of the animals. The study is based on the behavioral stereotype of detector dogs, consisting of the following sequentially performed techniques. At the start, for 1 minute the dog is encouraged to sniff a napkin containing the initial odor sample for the search in an open glass container. After the animal has memorized the starting odor, it is carried along open containers (comparative row) to alternately sniff the odor samples placed in them. When an odor test is detected among them, having a common source of origin with the test given at the start, the dog takes a signal pose developed by training - sits or lies down near this object.

Before each animal starts searching for a given smell, one of the specialists rearranges all objects in the comparative series, ensuring a random order of their location. The second specialist, who ensures that the animal sniffs the placed objects, is not informed about this order until the dog displays signal reactions (for the purity of the experiment).

An examination of the obtained samples for the presence of odor interferences that were not taken into account during the preparation of objects and that could affect the overall results of the analysis is carried out in relation to each biodetector. For this purpose, the detector dogs used are given an odor sample obtained from a person not involved in the incident as an initial sample for memorization and search. At the same time, in the comparative row, among the auxiliary odor objects, odor samples of the person being tested are placed.

Features of the procedural nature of odorological sampling consist in the use of its results in the process of proof.

The current practice of conducting odorological sampling as part of an expert study with in-depth analysis raises doubts. First, the sampling is carried out by a specialist who is not conducting any research. The range of its actions is limited to ensuring the optimal use of detection dogs. The process of identifying the desired smell is carried out by a biodetector. Therefore, the assertion that the real subject of the study of odor samples is a forensic specialist, armed with the necessary knowledge in the field of criminology, possessing methods for studying human odor traces and practical experience in their use in relevant situations, is, to say the least, unconvincing. From the fact that he carries out preparatory measures for sampling and then observes the operation of the biodetector, it does not naturally follow that he needs to evaluate everything that happens from the point of view of an expert.

Secondly, the theory of evidence does not allow the use of a detector dog in expert practice instead of a device, since it is impossible to put an equal sign between them. The technical means used during the examination must be scientifically substantiated: the principle of their operation is explained, the results of use are calculated, the procedure for checking the results obtained is described, etc. Nothing is known for certain about what happens in the dog’s brain when it recognizes the desired smell , it is currently not possible to verify the truth of the results obtained in any other way. These circumstances do not exclude the possibility of the emergence of objective factors unknown to the expert, which will naturally lead to the formulation of erroneous conclusions, therefore the dog cannot be used in expert research on a par with technical instruments.

Thirdly, the odorological examination reports provided to the investigator and the court do not contain information about the description of the set of individual characteristics displayed in the traces of odorous substances, based on the study of which the expert comes to the conclusion about the origin of these traces from the person being checked. This is explained by the fact that at present the specific composition of the substances that determine a person’s individuality and how a dog determines them have not been established.

Fourthly, expert practice knows only two types of identification: by materially fixed displays of the characteristics of an object and by signs of common origin. Recognition of the person being tested by smell by a biological detector does not fit any of them. Most of all, this procedure resembles identification by mental image (identification of sensations arising from the perception of the starting and target odors), which is used in criminal proceedings as identification.

Since a service dog cannot act as a subject of identification and as a device during an examination, and the results obtained with its use have a high degree of probability, there is a need to develop a different procedural form for conducting odorological sampling.

Due to the fact that the prosecution, defense and judges often do not have a clear understanding of the methods and capabilities of examining human scent traces and to ensure provisions for assessing evidence based on inner conviction and their direct examination (Articles 19, 105 and 386 of the Code of Criminal Procedure of the Republic of Belarus) , it is advisable to carry out odorological sampling as part of an independent investigative action. In this case, it is necessary to fulfill the following requirements: the sampling must be carried out in strict accordance with the methodology developed and tested in practice by specialists in the field of odorology and cynology, having a higher legal education or the necessary forensic training;

the investigator is obliged to exercise direct control over the preparation and conduct of the odorological sample;

during its implementation, the right of the victim or his representative, the suspect (accused) and his defense attorney to participate in the investigative action must be guaranteed;

the progress and results of odorological sampling must be recorded using video recording.

Only when such an investigative action is carried out can the investigator and interested participants in the criminal process directly perceive and correctly evaluate, and the court examine the results of the odorological sample. This will allow maintaining a high level of trust of subjects of legal proceedings in the evidence contained in expert opinions.

Introduction

Almost all objects of the material world around us have one or another smell, which is one of the properties of any object or substance layered on it. The “compass” in the world of smells for people and animals is the sense of smell - the oldest of the senses developed by nature in the process of the evolution of all living things. Even very small amounts of odorous substances or mixtures thereof can carry a large amount of forensically significant information. Thus, odor sensations received by a person through his own sense of smell (smells of burning, rotting, animals, medicines, perfumes, gasoline, etc.) are usually taken into account when inspecting the scene of an incident, objects, etc., and can be useful in search and evidentiary purposes.

In Russia, as in a number of other countries, the scientific foundations and technologies for laboratory identification of a person based on their scent traces are being developed. They are carried out on the basis of deep scientific research in the field of genetics, biology, zoology, chemistry, physiology, zoopsychology and other scientific disciplines. Taking into account foreign experience, Russian criminologists have developed the training of specialized dogs, invented a cryogenic-vacuum non-contact method for removing scent traces from carrier objects, and solved the problems of guaranteed control and deciphering the signal behavior of service dogs.

It is interesting to note that even the founder of criminology, Hans Gross, recommended that investigators determine “whether there is an odor, for example, of smoke, perfume, or any toxic fumes,” and suggested storing traceable objects in tightly closed glass containers or sealed tin cans.

The importance of scent traces for solving a number of forensic problems is due to the fact that they are formed almost continuously and as long as the source of the smell exists. These circumstances predetermined the formation forensic odology as a branch of forensic technology dedicated to working with scent traces, based on the provisions of odology - the study of the nature and mechanism of formation of odors, the methods of their recognition and use.

Biologists consider the release of odorous substances that characterize a person as the result of a stable metabolic function of the cells of his body, caused by a complex mechanism of intracellular transformations specific to a given organism, occurring under the strict control of the individual’s genetic program. Therefore, the individual smell of a person should be understood as a genetically determined property of the odorous substances of his blood and sweat, perceived as a specific, unique characteristic.

More details

A person’s personal smell is determined by factors that do not accompany his life, reflecting everyday life, activities, habits or the specifics of the environment, as previously thought. But the presence of such “additives” in odorous samples obtained from the subject can affect the results of the study, and therefore must be taken into account when conducting it. Since the composition of odorous components in scent traces is determined genetically, the smell of each person is individual and unique. It consists of odorous substances that individualize the subject, plus those that determine the biological species, gender, age, disease, physiological and emotional state of the body.

Superimposed on this basis are odor components associated with the consumption of food, alcohol, drugs, medications, as well as odorous substances determined by the level of personal hygiene of a person, the characteristics of the skin microflora, the activity of the sebaceous and sweat glands, and the perfumes and cosmetics used.

The smell of a person is always mixed with the so-called background odors emitted by damaged vegetation, soil cover, crushed small insects, etc. It is important that the background aromas, as well as the odors of different people, do not mix with each other and do not result in a new smell. Background impurities may include odorous substances from other subjects (for example, the victim), animals, industrial, household odors, as well as the aroma of the carrier object itself.

Using forensic techniques, it is possible to detect, seize, preserve molecules of human odor and keep them suitable for use for a long time.

Analysis of odor traces allows:

• • detect participants in the crime;
  • identify the individual odor of the same person in odorological traces taken from different crime scenes;
  • establish that the items found at the scene of the crime belong to the criminal;
  • confirm that the items seized from the suspect belong to the victim;
  • determine the origin of the smell from a specific person, etc.

The odorant analyzer is traditionally a service dog. Experiments have shown that dogs can easily distinguish people, including members of the same family, by smell. The uniqueness of the smell is genetically predetermined, therefore the individual component of a person’s smell does not depend on his diet, clothing or home environment. Physico-chemical devices are also used as analyzers, capable of identifying a spectrum of odorous substances, recording it and, with high sensitivity, determining the individual components of human secretions, whose odor is formed by highly volatile and sweat-fat components.

Classification of odor traces:

1) on the mechanism of formation and features of working with them:

• • unfixed (stored for only a few minutes and can only be used when working in hot pursuit, i.e. once);
  • fixed (can be stored from several hours to several years and can be used repeatedly).

2) by source of origin:

• • secreted by living organisms and plants;
  • emitted by objects of artificial nature (fuels and lubricants, perfumes, plastics, metals).

3) according to the moment of formation:

• • fresh (discovered within an hour from the moment they were left),
  • normal (detected within three hours),
  • old (more than three hours have passed since formation).

More details

In closed, unventilated areas, odor traces remain on highly absorbent media for up to two years. Odorological marks are stable in the cold, in the shade, in enclosed spaces, on porous, rough surfaces; They are preserved worse in the wind, on heated and smooth objects. On things and objects buried in the ground or snow, scent traces are present for up to several months.

Human odorous substances on footprints, shoes, crime instruments and the scene of an incident in an open area remain for 20 hours, and on personal belongings and objects - up to several days. The shelf life of odor traces depends on the volume and degree of ventilation of the room, as well as on the odor-perceiving properties of the location of the carrier objects.

Service dogs quite clearly “recognize” people by smell samples from rooms in which they were located for 10-15 minutes, as well as by smells taken even from small objects (matches, buttons, pins, etc.). Hair from various parts of the body and trimmed nails are effective in identifying items belonging to the suspect. If there are odors of other people in the room, this does not significantly affect the quality of the sample.

Working with scent marks- an important part of the inspection of the scene of the incident. It includes:

1. 1. studying the situation to identify possible locations of scent traces and ensure their safety;
   2. elucidation of the mechanism of formation of these traces;
   3. identification of objects on which scent traces could remain;
   4. the use of a service dog to detain a criminal in hot pursuit, to detect lost, abandoned or hidden objects with his scent traces;
   5. removal of trace-carrying objects or odorous samples from traces and other objects - sources of human odor;
   6. protocol and other recording of seized objects.

Odor traces are formed as a result of direct contact of various objects with a person. They can be taken from the body, clothing, things, documents, from volumetric and superficial traces of feet and hands, from obstacles that the criminal overcame or damaged, from the body and clothing of the victim, objects and instruments of crime, from the air of premises where the subject of interest to the investigation has been for a long time or stayed for a short time. Odor carriers also include hair and skin flakes separated from the body.

The main objects are carriers of human scent traces suitable for personal identification:

• • blood (including in dry spots),
  • hair (retains a person’s individual scent for decades),
  • sweat, personal belongings (worn items of clothing and shoes retain an individual odor from several days to several months),
  • various objects (means of committing a crime, weapons, etc.) that were in contact with a person for at least half an hour;
  • traces of shoes and feet on the snow and soil retain human odorous substances for up to one day.

Features of working with scent traces:

1. 1. creating conditions that ensure maximum preservation of odorological traces;
   2. limiting the number of participants in the inspection of the crime scene to only necessary persons;
   3. avoiding damage or contamination of traces with foreign odorous substances.

The search and removal of scent traces must precede work with any other traces or objects at the scene.

When inspecting the scene of the incident - the room, scent traces should be looked for first of all on:

• the place where the criminal was waiting for his victim;
• approaches to doors and windows from the outside and inside;
• places of struggle and where valuables were stored and from where they were stolen;
• safes, various seats, places of discovery of objects, instruments of crime, personal belongings of the suspect;
• ways of escape of the criminal;
• places where stolen goods are hidden (barns, garages, attics, basements, etc.).

When inspecting a car used by criminals, traces of scent should be removed from the seats, steering wheel, and objects they left there (cigarette packs, crumpled paper, handkerchiefs, ropes, bags in the trunk).

The procedure for removing scent traces

When removing odor traces, the included glass bottles with ground-in stoppers, sterile medical gauze wipes and sterile medical cotton wool included in the investigation suitcase are used. Collection of odor samples from traces is carried out using tweezers and clean rubber gloves, which will prevent clogging of traces with foreign odorous substances. First, the dry carrier object is slightly moistened with a spray bottle, as this promotes the release of odorous substances. Then the object in the places where the odorous trace is supposed to be localized is wrapped in a cotton napkin, and two layers of household aluminum foil are placed on top of it, after which it is pressed tightly to ensure good contact of the fabric with the object. Such mutual contact must last for at least one hour. When using activated carbon fabric as a sorbent, the contact time is halved.

After collecting odorous substances, the napkins (charcoal cloth) are removed from the items and packaged separately in clean glass jars or wrapped in several layers of foil. The jars are tightly closed with glass or metal lids. When removing trace-bearing objects, they must be wrapped in several layers of foil, taking care not to damage other traces: fingers, layers of microparticles, hair, etc.

If the criminal left personal belongings and objects at the scene of the incident, use tweezers or hands in rubber gloves to place each object in a separate new plastic bag, which is tightly tied. For better sealing, double polyethylene bags are used, in which scents can be stored for months without losing their individual qualities.

Odors taken and preserved in a timely manner can be sent by mail to make samples of the suspect’s belongings and objects. You can also send items of clothing (shirts, handkerchiefs, hats, shoes, socks, etc.), since they contain quite a lot of odorous substances. The selection of samples for comparative research is documented in a protocol for the collection of samples of odorous substances.

Samples containing particles of human odorous substances are placed in hermetically sealed containers for storage and subsequent use in the search for criminals. Service dogs quite clearly make samples of people based on such samples. For a reliable odorological sample, a few tens of cubic millimeters of air with molecules of odorous substances taken from a person or his trace are sufficient.

Since human biological secretions (blood, urine, saliva, semen, etc.) contain individual odorous substances, they are effectively used to sample things and objects with the help of a service dog. When biological secretions are found on objects and things that can be removed, they are placed in sealed containers. If discharge is found on the ground, then it is advisable to remove it along with part of the soil and place it in a sealable glass container. In cases where biological secretions cannot be removed along with an object or thing, it is recommended to take samples of odorous substances.

Forensic examination of human scent traces

To carry out an expert study, it is necessary to select comparative odorous samples from suspected comparative odorous samples. The investigator is usually assisted in this by forensic doctors. Since the purest source of odor traces is human blood, the physician takes 3-4 drops from the suspect’s finger, dries it on sterile gauze at room temperature and places it in a paper envelope.

The investigator can obtain comparative samples independently. To do this, the suspect (victim) places clean pieces of flannel (flannel, etc.) on the body: under the waistband of trousers, behind the collar, under the cuffs of the sleeves, ensuring close contact with the skin for at least 30 minutes. It is also permissible to use worn clothes and shoes of the person being checked, as well as his headdress. However, it should be remembered that Only the use of blood as comparative samples of human scent traces allows experts to make a definitive conclusion during identification. Control samples of cotton (charcoal) fabric used to collect odor traces (to take into account its background odor) are also provided to the expert.

The examination resolves the following questions:

1. 1. are there any traces of human odor on the presented objects (seized samples);
   2. they were left by one subject or several;
   3. what is the gender of the person who left the marks;
   4. are there any scent traces of this person in the collected traces of blood or on the hair;
   5. whether these traces originate from a specific individual;
   6. which of the presented items bears scent traces of the suspect;
   7. by whom among the suspects they were left, how long ago, etc.