Fingerprint examination

Dactyloscopic examination – a study of traces, prints (imprints) of the palmar surfaces of the hands (their elements) in order to establish their identity, the properties of the persons being checked, and to establish other factual data, which is carried out by an informed person.

Reflection – a reflection of a papillary sample (papillary lines) obtained in the process of rolling the palmar surfaces of the hands along the form of a fingerprint card in the process of obtaining samples for a comparative study or forensic registration.

Imprint – a display of a papillary sample (papillary lines), obtained by pressing the palmar surfaces of the hands to the form of a fingerprint card in the process of obtaining samples for a comparative study or forensic registration.

Random signs are signs formed in the trace during its formation and are not signs of the trace-forming object.

Altered features are features that experienced certain distortions during the formation of the trace.

Fingerprint films are special films for copying handprints treated with chemicals and their mixtures (fingerprint powders, sprays, etc.).

Details of the structure of papillary patterns are macroscopic morphological features that make up a sample of papillary lines (beginnings and ends of papillary lines, their merging and branching, etc.).

Details of the structure of papillary lines – microscopic morphological signs of irregularities (protrusions and depressions) of the edges of papillary lines (studied by endoscopy) and the configuration of the excretory openings of sweat glands on papillary lines (studied by poroscopy).

Reliable signs – signs, the mechanism of formation of which in the trace does not raise doubts in their adequate reflection in relation to the signs of the structure of the trace-forming object.

Samples (comparative objects) are the objects of examination by which identification is carried out.

Track-bearing objects are objects on which traces of hands are found or may be found.

The main (investigated) objects are identifiable objects of expertise.

A complex positive-negative trace is a trace formed by protruding and depressed parts of a trace-forming object in the process of one trace contact (in fingerprinting – papillary lines and interpapillary grooves at the same time).

Latent traces are traces invisible to humans in natural (unfiltered) light.

Localization – determination of the area of ​​the trace-forming object, on whichformed trace.

Interpapillary grooves are the depressed parts of each surface covered with papillary patterns.

The mechanism of trace formation is a certain sequence of actions, as a result of which traces are formed. It consists of trace-forming and trace-accepting objects interacting with each other due to the trace-forming force, and trace substance.

Negative traces – traces of hands formed by the suppressed parts of the trace-forming object (in fingerprinting – interpapillary grooves).

Papillary lines are convex parts of the skin surface covered with papillary patterns.

Positive traces – traces of hands formed by the protruding parts of the trace-forming object (in fingerprinting – papillary lines).

The trace substance is the substance that is formed by the interaction of the trace-forming and trace-receiving objects with the help of the trace-forming force. Volumetric traces are formed due to the substance of the trace-receiving object, surface traces are formed due to the substance of the trace-forming object or one of the objects (forming or perceiving) accidentally falling on the surface.

Traces of delamination are surface reflections of the external structure of the trace-forming object, which are formed due to the separation of a small amount of the substance of the next surface or foreign substances that are on this surface at the time of trace formation.

Traces of good quality – traces with a clear reflection of the flows of papillary patterns, reliable individual signs of their (papillary patterns) structure, individual signs of the structure of papillary lines (possibly in separate areas or in their absence), establishing their presence in a certain area of ​​the papillary sample, location, type , type, position, other characteristics

Traces of layering – surface traces of the external structure of the next object, arising due to the separation of a certain amount of the substance of the trace-forming object or foreign substances that are at the time of trace formation on its surface.

Traces of poor quality – traces with an indistinct display of papillary lines in samples or papillary patterns in general, superimposition of papillary lines on each other, their discontinuity, the presence of areas with unreflected parts of the lines, the inability to determine the reliability of individual signs, the presence of signs that can be defined as doubtful , their type, type, location and relative position, other characteristics.

Handprints – traces formed byapillary patterns of the palmar surfaces of the hands or their elements (nail, middle and main phalanges of the fingers, palms).

The trace-forming force is a mechanical force that determines the mutual movement of objects participating in the mechanism of trace formation.

Doubtful signs – signs, the mechanism of trace formation in the trace raises doubts about their adequacy in relation to the features of the structure of the trace-forming object (usually found in traces (track sections) of poor quality).

Qualitative and quantitative characteristics of signs – characteristics of signs, consisting of indicators of the frequency of occurrence of signs, from which their identification significance in relation to each other follows, their total number and the possibility of forming a complex of signs, which is individual and sufficient to recognize traces suitable for identification, establishing identities of compared objects.

Dactyloscopic examination solves the following issues:

  • detection of latent traces of human hands, establishment of the mechanism of their trace formation, temporary links between the formation of traces and the crime event;
  • recognition of the characteristics and properties of the persons being checked by the footprints of the hands;
  • Identification of a person by footprints, prints (prints) of hands.