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Trace Evidence

The term "trace evidence" is generally thought of as any type of evidence occurring in sizes so small that it can be transferred or exchanged between two surfaces without being noticed. The first scientist to formally articulate a philosophical foundation for transfer-evidence occurrence was the Frenchman, Edmond Locard (1877-1966): The dust and debris that cover our clothing and bodies are the mute witnesses, sure and faithful, of all our movements and all our encounters.

Wherever he steps, whatever he touches, whatever he leaves, even unconsciously, will serve as silent witness against him. Not only his fingerprints or his footprints, but his hair, the fibers from his clothes, the glass he breaks, the tool marks he leaves, the paint he scratches, the blood or semen he deposits or collects - All of these and more bear mute witnessagainst him. This is evidence that does not forget. It is not confused by the excitement of the moment. It is not absent because human witnesses are. It cannot perjure itself; it cannot be wholly absent. Only its interpretation can err. Only human failure to find it, study and understand it, can diminish its value." (Crime Investigation , Kirk, Paul. L, New York : Interscience Publishers, 1953.)

The dust and debris that cover our clothing and bodies are the mute witnesses, sure and faithful, of all our movements and all our encounters.

EVIDENCE HANDLING   Video - Trace Evidence Guidelines

Fibers And Textiles
Comparison of known/unknown fibers

Fracture Match
Reconstruction of broken materials to determine if common origin

General Materials
Characterization of unknown solid materials or residues

Glass
Comparison of questioned glass to suspected sources of origin

Gunshot Residue
Analysis for the presence of gunshot primer residue

Hair Analysis
Comparison of questioned hair with suspected sources of origin or characterization of hair for investigative purposes

Paints and Coatings
Analysis of paint and comparison to known samples

Plastics and Polymers
Comparison of plastics and polymers.