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Collecting DNA Evidence at Property Crime Scenes

Profile Types

Profile Types

CODIS operates three database levels: local, state and national. Within each level, there are multiple categories known as indices that include convicted offender DNA profiles and unsolved crime scene evidence (forensic profiles), among others.

Convicted Offender and Arrestee Indices

Convicted offender and Arrestee profiles account for most of the entries in a state's DNA database. Individual state legislation determines the ability to collect DNA from individuals arrested for qualifying offenses and for the qualifying offenses for which convicted persons must submit a biological sample for inclusion in the database.

Forensic Index

The second most common entry in DNA databases consists of forensic profiles. These are profiles developed from evidence in forensic cases. The forensic profiles are entered via CODIS to search for a match, and generate an investigative lead. Significant numbers of the forensic profiles entered by individual states into CODIS are the probative profiles from cases where the individual who committed the offense is not known, commonly referred to as unsolved cases. Additionally, some states also enter forensic evidence profiles that match the reference profile of the suspect in that case (solved cases).

Other Indices

Based on state laws, some state agencies collect and maintain DNA samples from individuals arrested for certain offenses. Some states and local agencies maintain a suspect database.

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