Statistical Evaluation of Torn Duct Tape

This study will attempt to obtain statistical inferences on the uniqueness of duct tape that has been torn and on the subsequent attempt to match it to the tear. Duct tape is frequently used in crimes of violence and has a significant evidentiary value when torn ends left at the scene are physically matched to the torn end on a roll of duct tape that may be recovered from a suspect. However, a review of the literature on physical matching illustrates that when the final determination is made, the only statement that exists is that the tape physically matches. There is neither supporting statistical data nor are there any objective criteria as to what constitutes a match or its associated error rate. This study will compare approximately 1,000 duct tape tears and if time permits additional duct tape cuts made by scissors. These comparisons will be made by graduate student researchers. This proposed study will provide error rates and attempt to develop objective criteria for the physical matching of duct tape samples. ca/ncf