Identifying Differences Between Cut Marks Made on Bone by a Machete and Katana: A Pilot Study.

Area of Science:

• Forensic Science
• Bioarchaeology
• Anthropology

Background:

• Distinguishing tool marks on skeletal remains is crucial in forensic investigations.
• Previous research has focused on general characteristics of bone trauma, but specific weapon signatures require further elucidation.

Purpose of the Study:

• To identify and differentiate cut mark characteristics produced by a machete and two katanas on various bone types.
• To establish statistically significant associations between specific morphological features and weapon types for forensic application.

Main Methods:

• Experimental cutting of Sus scrofa (pig) rib, flat, and long bones using one machete and two katanas.
• Systematic recording of cut mark characteristics including flaking, feathering, peeling, micropeeling, chattering, microcurvature, scoop defect, and exit notch.
• Statistical analysis using Pearson's chi-square tests and logistic regression to determine associations between characteristics and weapon types.

Main Results:

• Machete cut marks were significantly associated with scoop defects on rib bones (93% classification), micropeeling on flat bones, and chattering on flat and long bones (p < 0.001).
• Katana cut marks showed significant associations with microcurvature on flat and long bones (p < 0.004) and exit notches on flat and long bones (96% and 100% classification, respectively; p < 0.001).

Conclusions:

• Specific morphological features can reliably differentiate between machete and katana-induced bone trauma.
• The identified associations and developed logistic regression models offer valuable tools for forensic casework involving hacking trauma identification.