A comparative analysis of the deterioration rates of textiles and their role in determining postmortem interval

A predominant problem that must be solved in the medico-legal field of forensic science is when death occurred. Accurate determination of postmortem interval (PMI) enables investigators to narrow the time frame of events for a case, a crucial step for law enforcement in forensic analysis. Multiple taphonomic variables affect the decay rate of the human body and the subsequent formation of PMI estimates. Employing a two-phased strategy, this study seeks to analyze the correlation between the deterioration rates of various fabric types in relation to determining the PMI of a forensic case. First, an analysis was completed based on a comparative evaluation of clothing curated by the Louisiana State University Forensic Anthropology and Computer Enhancement Services (FACES) Lab. Second, a field study exploring the deterioration rates of cotton and polyester was initiated in Baton Rouge, Louisiana, and Fredericksburg, Virginia. The eight-month field study analyzed the influence of varying climates and burial conditions over time. Results indicate that a linear predictive model of deterioration is not possible because deterioration is not linear. However, as demonstrated by both research projects, characteristics of fabric deterioration are observable and can be assessed to form PMI estimations. In the FACES Lab research project, examination of only clothing offered 82% accuracy in determining PMI. When taken in consideration with other evidence, particularly skeletal materials and knowledge of the deposition context, the examination of textiles serves as an illuminating, complementary role in the formation of PMI estimates