Forensics is the most important and practically significant science, which has a direct impact on the investigation of crimes. The forensic system includes a wide variety of examinations and studies that are interesting in the study and analysis. An example is the study of transport tracks, the so-called trasological examination. We will pay attention to it and note all the details of its implementation, as well as the classification.
The concept of trasological expertise
This is one of the most common types of forensic expertise. Trasological research refers to the investigation of traces of a crime by a person who has special knowledge in the field of science, technology, and art. Moreover, as a result of the study, a conclusion is formed, which in the future can be used as evidence in the case. There are many types of such expertise:
- Fingerprinting - traces of fingers and toes.
- Examination of human teeth.
- Examination of traces of clothing or some of its elements.
- Examination of fillings and traffic jams.
- Examination of animal tracks.
- Examination of vehicle tracks.
We will talk in more detail about the latter form.
What are traffic tracks?
In the science of forensics, traces of vehicles are those traces that convey the appearance and structure of a certain part of a vehicle. It can be a body, tread, side, or something else. Traces may also indicate a part that has separated from the whole vehicle. Note that the traces also include substances that are necessary for the normal operation of the machine. This is brake fluid, any lubricating oils, antifreeze and much more. The most common at the scene is the track of the wheels.
Significance of detected traces
The study of vehicle tracks is of great importance in practical work, it affects the process of proof and the completeness of the circumstances of the case. First of all, with the help of research, you can determine:
- Which group of vehicles does the track belong to? The brand of the machine, type, model is analyzed and installed.
- Establish a correspondence between a specific vehicle on the traces found and parts and parts separated from it.
- To establish the presence of malfunctions and malfunction of some parts and mechanisms of transport.
- The nature and nature of the damage that occurred on the vehicle as a result of the accident.
- Some circumstances of the case, which may be of great importance for the case. This is the speed of the transport, its location in relation to other vehicles at the time of the collision, the size and area of the cargo carried, and much more.
As we can see, traces of vehicles can say a lot about the essence of what happened, form the evidence base.
Trace detection
First of all, before each examination, it is necessary to identify and remove one or another trace from the scene. Detection of vehicle tracks begins from the moment of visual inspection of the scene. Careful inspection is important in this process. In this case, the investigator must mentally imagine what kind of vehicle model it could be, determine the boundaries of the scene, objects that are important for the case and require investigation.
There are times when the tracks are not so pronounced and large. If they are hardly visible or completely invisible to the naked eye, then the employee uses special magnifiers.
Where can vehicle tracks be left? By and large everywhere: this is a roadside, a ditch, the surface of the road, structures and structures that are located near the scene of the incident. They can also be on clothing, the body of the victims, trees and any objects that are within the boundaries of the territory.
Tracing
Upon departure to the scene, the investigator draws up a protocol for the inspection of the place. It describes the location of the tracks in relation to other objects, clearly establishes the boundaries. The nature and dimensions of the trace found are described in detail. This takes a picture. In forensics, there are several types of photographing. The main requirement is the detail and detail, as well as the clarity of the photo. Not only the investigator leaves for the scene of the incident, but the entire task force, including an expert. Assessing the situation, he decides on the need for additional fixation of the trace.
That is, the main method of fixation is the production of photography, with the help of which a subsequent assessment and examination of the trace occurs. There is also a method such as a cast. It is made from a solution of gypsum, applied to the trace and subsequently transmits the transport trace on a real scale. The nuance is that such a solution can only be poured over small distances - no more than 40-50 cm. For this purpose, if the track is large, it is first divided into several sections. Dividing into sectors occurs using glass, plywood, which are pressed into the structure of the track. Each of them is subsequently separately recorded.
If there are traces of tire spikes, then copying occurs with the help of a rubber sheet, previously it is cleaned with sandpaper, photo paper and adhesive tape are used. This process is very important, therefore, the help of specialists and experts is used.
Types by type of transport that left a mark
The classification of vehicle tracks in theory is very multifaceted, there are many reasons why traces are divided into types. The most common reason is the type of transport that left a mark. In this division, traces are highlighted:
- Non-rail vehicles, for example, a car, trolley, bus, motorcycle.
- Road transport, for example, sledges, carts.
- Devices that move due to physical force are bicycles, sledges, carts.
- Rail transport, for example, metro, tram, train.
As we see, this classification is very generalized and multilateral. In turn, each species is divided into several species.
Views of the object that left a mark
Consider the types of traces of vehicles that are allocated depending on what left this trail. In this classification, there are:
- Traces of a part or detail of a vehicle. For example, a track of a wheel on a roadway, a track of a bumper on an obstacle.
- Trace of an item that has separated from the vehicle. For example, these are fragments of glass that are separated from the headlights of the diffusers, part of the radiator grille, fragments of the bumper and much more.
- Substances that are in the paintwork, drops of oil or liquid from the cooling system.
Depending on the quality of the road surface, the traces of vehicles in forensics are divided into surface (traces of layering or delamination) and three-dimensional (deformation of the object perceiving the track occurs).
Questions to the expert
Carrying out a study of the tracks of vehicles, the expert answers the questions that were raised by the investigator in the decision on the production of the study. These issues typically include:
- What kind, model of the car does this mark leave?
- Which tire model could leave such a mark, as well as which wheel was in transport?
- In what direction did the object move, in what place did the collision occur? At what angle was it, what was the relative position?
- Are these traces left by this vehicle (if the investigator found the alleged vehicle)?
- Are the found traces formed by this agent?
And many other questions that are posed depending on the situation and the nature of the trail. The investigator may not be able to cope in posing the questions, formulating them vaguely. For this purpose, the help of specialists is used.
The value of expertise
Examination of vehicle tracks in the science of forensics is called transport and traological research. It is of great importance, because no matter what the nature of the incident, traces of transport are very common. In today's world, no one can do without transport, be it personal, work or public. That is why the examination will determine the circumstances of the case, narrow down and detail the investigation process, form the subject and scope of evidence. This suggests that we need to constantly develop and improve this area of knowledge, this will allow us to conduct the most effective and productive traological examination.