Cold Hit
Definition
A database match between a crime-scene DNA profile and an offender or arrestee profile where no other investigative lead identified the suspect. Cold hits produce an investigative lead, not a conviction: the match must be independently verified and the profile must be admissible.
- Type
- Database match, DNA profile
- Preceding lead
- None; suspect identified only via the database
- Legal status
- Investigative lead, not standalone proof
- Requirement
- Independent verification and admissibility check
Common questions
How does a cold hit differ from a confirmatory DNA match in an ongoing case?+
A confirmatory match tests a known suspect already identified through other evidence, while a cold hit is how the suspect was identified in the first place, purely from the database search, so it carries a different evidential weight and typically triggers a fresh confirmatory sample and full profile comparison.
Why can't a cold hit alone secure a conviction?+
It shows only that a profile in the database matches the crime-scene sample; investigators still need to independently corroborate the person's connection to the crime, since a database match alone does not establish how or when the DNA was deposited.
Related terms
- Bharatiya Sakshya Adhiniyam 2023 (BSA)
- India's current evidence statute, which replaced the Indian Evidence Act 1872. Section 63 of the BSA governs electronic records and requires a...
- CODIS
- The FBI's Combined DNA Index System, the US national STR-based forensic DNA database. Contains profiles from convicted offenders, arrestees, and unidentified crime-scene...
- Familial Searching
- The deliberate use of partial DNA profile matches in a forensic database to identify biological relatives of an unknown contributor, on the...
- Proportionality
- The legal principle, central to European human rights law and to many constitutional systems, that any interference with a fundamental right must...
- STR Profile
- Short tandem repeat profile: the numerical representation of repeated DNA sequences at a defined set of loci, used to generate a forensic...