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transfers between a suspect and carpet and/or other environmental fiber donors at a crime scene.

Questioned and known fibers are examined and compared using microscopic and analytical instrumental

techniques much like paint is analyzed. As with most trace evidence, individual fibers cannot be said to

come from a particular item of clothing or fabric. However, finding fibers with the same generic

composition (e.g. polyester), color, shade, and morphology(shape) on the suspect with known fibers from

the scene can be of significant value in both investigation and prosecution of a criminal case. Fiber analysis

has often demonstrated that the body of an individual was likely transported in the trunk of an automobile.

Flammable liqiuds are also a type of trace evidence. When arson investigators are called to the scene of a

fire one of their foremost methods to determine that a suspicious fire was deliberately started is by taking

samples from the burned scene and submitting them to Arson examinations. Burned debris samples are

taken by the investigator in airtight cans. The labs then perform careful extractions on the contents of the

cans. These extracts are analyzed using sophisticated and very sensitive instrumental techniques. In some

cases, petroleum residues less than one microliter (0.00004 ounces) can be found in the debris from the

scene. Since most of these are not naturally ocurring in nature the prosecutors can argue that it was put

there.

The last type of trace evidence covered in this paper is fingerprint evidence. Some Forensic Scientists

perform examinations on various items submitted to them, as well as processing crime scenes, to determine

if usable fingerprints are present. The labs use classical fingerprint processes such as dusting powders,

ninhydrin solutions and “Superglue” techniques. They also use the latest advances in detection technology

such as laser lighting and computer enhanced imaging. These later techniques are valuable in examining

very faint latent prints, smeared/smudged prints, and prints on multicolored surfaces. They are also

extremely useful in the examination of blurred surveillance photos and other photos that may be otherwise

deemed useless.

Trace evidence is a very important part of forensic science and plays a large role in identifying perpetrators

of crime. One of the best values of trace evidence is that its deposition is almost always unnoticed. Its

importance can not be minimized however, as the article clearly shows. Many different scientific

techniques are utilized to analyze trace evidence as hopefully, I’ve shown.

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