What defines a tool mark?

A tool mark is defined as evidence of an impression, cut, or abrasion caused by a tool. This definition encompasses the physical characteristics left by a tool when it interacts with a surface, which can provide crucial information in forensic investigations. Tool marks can be classified into two main categories: impressions and striations. Impressions occur when a tool makes a direct indentation on a softer surface, while striations are fine lines that appear on a surface due to the tool's movement, helping forensic experts match the tool to the mark.

Establishing the presence of a tool mark and analyzing its unique features allows forensic investigators to link a specific tool to a crime scene, which plays a critical role in criminal investigations and prosecutions. This connection can help establish that a suspect had contact with a crime scene or was involved in the commission of a criminal act.