Toolmark Evidence Collection
Physical Evidence Bulletin
California Department of Justice, Bureau of Forensic Services
See also the instructional videos on "Evidence Collection"
Purpose
Purpose The physical evidence bulletin is a guideline intended for law enforcement agencies to follow in order to submit evidence to BFS Laboratories. Physical Evidence bulletins are not intended to be used in lieu of training in the collection of evidence.
The Bureau of Forensic Services provides analytical support to law enforcement agencies through the examination of toolmark evidence. A toolmark is any impression, scratch, gouge, cut, or abrasion made when a tool is brought into contact with another object. Toolmarks can take the form of a negative impression (stamping type) or abrasion (friction type) mark. Some marks are combination of both features. Laboratory examinations and comparisons of tools from a suspect, with toolmarks recovered from a crime scene, can often provide conclusive evidence to link a suspect to a specific crime.