An assessment of the reliability of cut surface characteristics to distinguish between hand-powered reciprocating saw blades in cases of experimental dismemberment.

An assessment of the reliability of cut surface characteristics to distinguish between hand-powered reciprocating saw blades in cases of experimental dismemberment. J Forensic Sci. 2020 Nov 23;: Authors: Martlin B, Rando C Abstract Criminal dismemberment is most commonly committed with a variety of hand-powered saws. These saws leave characteristic marks upon the bone that can assist in the identification of the weapon utilized. The current study provides frequencies of presentation of ten cut surface characteristics and examines intra- and interindividual variation between three hand-powered reciprocating saws. Pig radii were used as a proxy for human remains. 42 cut surfaces were created with three hand-powered reciprocating saws by the same researcher. Cut surface characteristics were assessed macroscopically, microscopically and with Scanning Electron Microscope (SEM), as well as photographed with Reflectance Transformation Imaging (RTI). Cut surface polish is the only characteristic that demonstrates consistently significant difference between saws. Five characteristics demonstrate some variation between blades: entrance shaving, breakaway spurs, breakaway notches, pull-out striae, and tooth hop. Four characteristics demonstrate no difference between blades: cut surface striation shape, cut surface striation regularity, harmonics, and exit chipping. Tooth hop is the most reliable characteristic for differentiating between blades...
Source: Journal of Forensic Sciences - Category: Forensic Medicine Authors: Tags: J Forensic Sci Source Type: research