Fibers And Textiles

Fiber and textile evidence can provide strong evidence of an association in criminal cases. The individual microscopic fibers that comprise the variety of textile materials in the world can be transferred from person to person and place to place, indicating what environment someone has been in. These fibers are compared to suspected sources of origin in the GBI crime laboratory using a rigorous protocol which includes stereo, brightfield, polarized light, fluorescence and comparison microscopy, melting point determinations, Fourier transform infrared microspectroscopy (FTIR) and microspectrophotometry (MSP). Matching fibers between two sources indicate they were in contact. Carpet and upholstery fibers can be recognized as such and can provide information that may aid an investigator in reconstructing a crime or locating a suspect.

It is the job of the forensic fiber examiner to be familiar with all of the different types of fibers on the market and to know which are most commonly used and which are rare. This is often a daunting task as the textile market is constantly changing, but this type of information is critical when discussing how significant a fiber match is during courtroom testimony. Analysis of fibers has played a major role in solving several high profile cases, including the Atlanta murdered and missing children cases in the early 1980's.

Green carpet fibers found on victims were later linked to carpeting found in the home of convicted killer Wayne Williams. The fibers were traced to the manufacturer who provided investigators with information about customers who had purchased that style of carpet.

Fiber examiners also perform examinations to determine if garments have been cut or torn. This becomes important in sexual assault cases where there is a question as to whether the act was consensual or forced.