The branch of genetics that deals with the application of genetic knowledge to legal problems and legal proceedings.

Forensic genetics is also a branch of forensic medicine which more broadly investigates the application of medical knowledge that were applicable to legal matters.

This is not a new field. Long before the era of DNA fingerprinting investigators used blood grouping, HLA typing, and other tests of genetic markers in blood to try to determine who did it (and, more often, who did not do it).