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Data and Communication Flow in CODIS

NCJ Number
Date Published
March 2018
2 pages
This paper, which is part of the training and technical assistance offered to grantees under the Sexual Assault Kit Initiative (SAKI), describes the architectural indexes and communication flow within the Combined DNA Index System (CODIS), which is a dynamic system that provides aid in investigations that yield unknown DNA profiles investigators submit to a tiered architectural system that encompasses a network of DNA databases of known and unknown persons who have been involved in law enforcement investigations.
The tiered architectural network consists of local indexes that flow into their respective state index, whereby eligible DNA profiles flow into the National DNA Index System (NDIS). These architectural indexes further compose searchable indexes. The DNA profiles housed in these searchable indexes consist of DNA profiles of individuals convicted of crimes; DNA profiles of arrestees, based on state law; and DNA profiles of unknown persons taken from crime scenes and not matched to a victim, suspect, or elimination samples. A "hit" occurs under the following conditions: 1) when the DNA profile of an unknown suspect is linked to the DNA of an unknown suspect from another crime, and 2) when the DNA of an unknown person is matched to a known person in any of the CODIS databases. "Hits" are reviewed to verify the match or consistency between linked profiles and the eligibility and qualification of the samples. In some situations, samples may be pulled and reanalyzed. After verification, a written notification of the investigation aided will be maintained for records and provided to the investigator, usually in the form of a CODIS hit report. 5 references

Date Published: March 1, 2018