Familial Searching

CODIS Searching Criteria

When an evidence profile undergoes a traditional CODIS search, the search criteria are relaxed using something called “moderate stringency.” Every laboratory strives to obtain the complete DNA profile for each sample. Sometimes samples are degraded or of insufficient quality to yield a complete profile. CODIS searches are conducted under moderate stringency to report matches between incomplete profiles. Because of this relaxed criteria, less than complete or perfect matches occur, much like the Automated Fingerprint Identification System (AFIS) produces a list of candidate fingerprint matches. These “partial matches” occur quite infrequently and do not often produce viable investigative leads.⁸

⁸ Find a more thorough discussion of “partial matches” and their relationship to familial DNA searching at the Denver District Attorney website »