Clothing Fibers as Evidence. A Study of the Frequency of Occurrence of Blue Wool Fibers

It is common knowledge that loose fibers of all varieties adhere easily to clothing, and that when two sets of clothing come in contact, some fibers from each will be transferred to the other. This transfer will be greatest for the shorter and less conspicuous fibers, and its amount will depend largely on the adherent qualities of the cloth involved. In most crimes of violence, the clothing of the perpetrator contacts, sometimes forcibly, that of the victim, often for relatively long periods, as in certain assaults, sex offences, etc. Moreover, in crimes that do not involve violence, fibers are often available as significant evidence. Thus clothing fibers may often be removed from hit-run cars, window-sills, furniture, and the like. The significance of cloth fragments has been frequently studied, and matching of torn edges, thread counts, and similar procedures have been the means of solving numerous crimes. The occurrence of such propitious evidence as a piece of cloth is of negligible frequency as compared with that of detached fibers. Yet, the latter has received little attention in the literature of criminology and little, if any, quantitative study. In this paper is reported a study of the frequency of occurrence in men's suiting of the various types of blue wool fibers. These were chosen because blue is the most common color found in men's suit cloth, and wool makes up the bulk of most of the cloths used. When it is possible to give the average frequency of occurrence of each particular kind or color of fiber in an individual's clothing, it will be practical to calculate the probability that two sets of clothing have been in contact based on the number of such fiber species which have been transferred or found in common between the two sets of clothing in question. In one case investigated in this laboratory, the clothing of a victim, that of two suspects, and residues from the scene of the crime were studied for the common occurrence of identical fibers

Archaeology · Clothing · Composite material · Geography · Wool · Forensic and Genetic Research · Materials Science