Virginia Department of Forensic Science
DNA Databank Statistics
Databank Hits
Offender/Arrestee Samples in Database
Notes
- Total Hits: 5,835
- Total Samples: 302,098
- To see yearly totals, point mouse cursor over the corresponding bar in the above charts.
Crimes Solved/Assisted by Type
Total Investigations Aided: 5,694
Previous Criminal Conviction of Offenders Identified
Total Offender Hits: 5,065
The graph at the top demonstrates the dramatic impact that the size of the convicted offender sample database has on the hit rate to non-suspect cases. A hit occurs when the DNA profile from a crime scene sample with no suspect matches a DNA profile in a database of previously convicted offenders, a database of samples from those individuals arrested for specified crimes, or a database of other crime scene profiles. A record breaking 106 hits were achieved in the month of March, 2005.
A decision in 1998 to enter into a contract with a private laboratory to run backlogged convicted offender samples for three years combined with grant funding provided by NIJ, which allowed the Department to continue outsourcing the analysis of convicted offender samples into the summer of 2004, resulted in essentially no backlog of convicted offender or arrestee samples. The Department remains fairly current on the in-house analysis of these samples, and Virginia's databank now contains more than 302,000 offender and arrestee profiles.
It is the combination of these activities that led the Department of Forensic Science to score 283 hits by the end of 2000, an additional 308 hits in 2001, 445 hits in 2002, 608 in 2003, 695 in 2004 (average 58 hits per month), 810 in 2005 (average 68 hits per month), 612 in 2006 (average 51 hits per month), 799 in 2007 (average 67 hits per month) and 811 in 2008 (average 68 hits per month). For the first eight months of 2009, 464 hits were made to the databank. For 2003, 63 hits were made to the Arrestee Database (established January 1, 2003); in 2004 an additional 68 hits were made to arrestees, and in 2005 there were 107 arrestee hits. In 2006, 87 hits to arrestees were made. In 2007, there were 67 hits to arrestees. In 2008, thre were 91 arrestee hits. For the first eight months of 2009, 60 hits to arrestees were made. The first hit to the Arrestee Database occurred after the upload of the first 80 samples into the database! As of August 31, 2009, a total of 543 hits to the Arrestee Database had been obtained. 89 of the hits to arrestees were associated with sexual assault cases.
- Approximately 80% of hits would have been missed if the Databank was limited to only violent offenders.
- Approximately 40% of violent crimes solved were perpetrated by individuals with previous property crime convictions.
- DNA Databanks are most effective with inclusion of at least all felons and applied to all forms of cases.