The transfer of fibres via weapons from garments

Stabbings have been reported as the most frequent violent crime in countries where there is a severe restriction on obtaining firearms, such as the United Kingdom. Knives, scissors, and screwdrivers, as studied in this research, are among the most commonly encountered weapons involving stabbing events. When any of these implements are used in a stabbing, there is potential for the garment(s) worn by the victim to be damaged. In such an instance, there is an opportunity for fibres to be transferred to the weapon used, thus providing forensic evidence of proof of transfer from the victim’s clothing to the weapon. This can offer valuable information in establishing what weapon was used to harm the victim through linking fibres from the victim’s garment(s) to a weapon recovered from a suspect.

This research simulates vertical stabbings - performed by a human participant – in to a polystyrene block supporting the clothing (essentially acting as the victim’s torso), to reflect an authentic scenario. The aforementioned weapons were used along with 3 varieties of garments (cotton, polyester and a linen/viscose mix) offering different characteristics of shedability and structure for the simulated stabbings. Low power microscopy was utilised to view the transferred fibres. The amount of fibres transferred on to the implement were recorded for each repeat. 2,279 individual fibres were found over 10 repeats from the knife in relation to the linen/viscose garment. This was the highest amount of transference found with the lowest number attributed to the screwdriver-polyester relationship, providing 320 recorded fibres over 10 repeats. The findings of this study suggest that the number of fibres transferred is not only related to the shedability of the garment but also the surface area characteristics of the receiving weapon and the ability for the garment to tear.