The effect of fabric and stabbing variables on severance appearance

• The examination of fabric severances may provide valuable information to a forensic investigation.
• Two fabrics commonly used in the manufacturer of T-shirts, selected for fabric extension and elasticity variables.
• Severances created by male and female participants and included knife withdrawal.
• Severance length was affected by participant sex, fabric type, fabric laundering and knife type.
• Important observations regarding human participant variability.

During a stabbing, apparel fabrics are usually damaged and may be penetrated. Despite numerous studies considering forces required to penetrate skin and human stabbing performance, none have systematically evaluated which variables affect severance appearance from a textile science perspective using a human stabbing participant assessment. Although the human performance aspects of stabbing attacks have been previously studied, there has been a bias towards male assailants. The effects of fabric elasticity and tension applied have been identified as major factors influencing the severance profile in the fabric resulting from a stab attack. However, previous studies have considered limited fabric types with little emphasis on the physical and mechanical textile properties. The purpose of the current research was to use a human participant study (male n = 5; female n = 5) to determine the effect of fabric extension (0%, 10%) on the severance profile. Fabric type (single jersey; 100% cotton; 93% cotton/7% elastane), age (not laundered; laundered 60 times) and knife type (carving, bread) were also considered. Severance length was affected by participant sex, fabric type, laundering and knife type. The severances formed in this study were not significantly affected by the amount a fabric was extended when stabbed. Variability was observed in the severance appearance among participants where prior training influenced the angle of impact and knife withdrawal technique.