Re-examining the material with more advanced forensic tools that weren't around during the initial investigation is one approach. This may involve the use of forensic techniques such as fingerprinting, ballistics, and genetic testing.
Witness statements can be reviewed, and new witnesses can be interviewed who were not previously questioned. In the hopes that someone may come forward with information that can help solve the crime, law enforcement officials may also release new information or revive the investigation.
To broaden their understanding of a case, police enforcement organizations can collaborate with private investigators, academic researchers, or other professionals.
Generally, cold case investigative tactics might differ based on the nature of the case itself, the strength of the evidence, and the agency's resources.