FEATURES OF EXPERT RESEARCH OF TRACES FROM THE ACTION OF FOREIGN OBJECTS IN LOCKS WITH A LEVER LOCKING MECHANISM

The features of an expert study of traces from the action of foreign objects (master keys) in locks with a lever locking mechanism are considered. Consideration of a specific expert study is relevant, it describes and illustrates in stages the mechanism of trace formation of traces from the action of foreign objects, which remain on the external and internal surfaces of the lever mechanism of the lock, which further affects the process of identifying the trace-forming object during the identification forensic-traceological examination. In the process of conducting an expert study, the main stages of the forensic-traceological examination of traces from the action of foreign objects were analyzed. The types, types, structure, locks with a lever locking mechanism are considered. On the example of traces left from contact with a foreign object (master key), general features are analyzed that make it possible to determine the group belonging of a trace-forming object. The mechanism of formation of traces left on the external and internal surfaces of the lever mechanism of the lock has been established. A comprehensive assessment of the research results, scientific justification, the origin of the established signs and the formulation of conclusions were carried out. In the stages considered, examples of the description of objects of study, traces left by foreign objects and the course of establishing the group belonging of a foreign object (master key) are given. Traces from the impact of a foreign object (key, selected or counterfeit key) are traces that lie outside the contact surfaces of the full key. In addition, they differ in nature (direction of action, characteristic brilliance, location, etc.) from the traces formed by the action of the full key, and traces of an industrial nature. However, the vast majority of traces from the action of foreign objects, especially those of a matched or counterfeit key, lie within the contact surfaces of the complete key. These traces are similar in shape and dimensional characteristics to the traces of the complete key, causing difficulties in distinguishing them, especially in the absence of a specific foreign body during the study. In addition, traces that accidentally appeared during the manufacture of the lever mechanism and are not due to the technical process of its manufacture (deformations on the broach, accidental contact of the cutting edges of the tool with parts of the lever mechanism, traces formed during compilation) can also be attributed to a separate group, it is also possible to erroneously consider traces from the impact of foreign objects.