NCJ Number
226553
Journal
Journal of Forensic Sciences Volume: 54 Issue: 2 Dated: March 2009 Pages: 328-338
Date Published
March 2009
Length
11 pages
Annotation
This study examined the organic composition of electrical tape as a complementary means of distinguishing tape brands in addition to a determination of the microtexture and elemental composition of the backing of electrical tapes.
Abstract
In separate studies, two fragments of blast-damaged tape were correctly assigned to their brand of origin, and discriminant analysis was used to quantitatively associate or exclude tape samples from two bombing cases. The accuracy rates for energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIS) were similar (86 percent and 88 percent); the same brands were confused when attempting discriminant analysis (DA). DA based on FTIR analysis of the adhesive was significantly more accurate (97 percent). A direct comparison of EDS and FTIR using 47 rolls of tape with clear adhesive indicated that FTIR analysis was generally superior to EDS. A postblast study demonstrated that DA could correctly associate blast-damaged tape to its brand of origin, particularly when both EDS and FTIR were used to cross-check such a conclusion. The descriptions of materials and methods address tape exemplars, instrumental analysis, data analysis, method validation, and postblast study. 8 tables, 13 figures, and 12 references