WASHINGTON, DC (8/9/18) – On the heels of its approval for use by the Los Angeles County Sheriff’s Department and Washington State Patrol, STRmix™ – the sophisticated forensic software used to resolve mixed DNA profiles previously thought to be too complex to interpret – has been approved for use by Signature Science and the San Francisco Police Department.
A subsidiary of the Southwest Research Institute based in Austin, TX, Signature Science is a scientific and technical consulting firm, providing multi-disciplinary applied research, technology design and development, and scientific, technical, and operational services to government and industry.
The San Francisco Police Department (SFPD) is the city police department for both the City and County of San Francisco, CA. The 11th largest police department in the U.S., SFPD serves an estimated population of 1.2 million, including the daytime-commuter population and thousands of other tourists and visitors.
Thirty-six federal, state, and local agencies throughout the U.S. now routinely use STRmix™ to resolve DNA profiles, including the Federal Bureau of Investigation (FBI) and the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF). STRmix™ is also in use in 14 labs in Australia, England, Scotland, Ireland, Canada, and New Zealand, and in various stages of installation, validation, and training in more than 50 other U.S. labs.
“Since its introduction in 2011, STRmix™ has gone from being regarded as an experimental technology to the broadly accepted norm in cases in which forensic DNA software is required to resolve mixed DNA profiles,” says John Buckleton DSc, FRSNZ, Forensic Scientist at the New Zealand Institute of Environmental Science and Research (ESR). Dr. Buckleton developed STRmix™ in collaboration with ESR’s Jo-Anne Bright and Duncan Taylor from Forensic Science South Australia (FSSA).
STRmix™ works by using standard, well-established statistical methods to build up a picture of DNA genotypes that, when added together, best explain an observed mixed DNA profile. STRmix™ then enables users to compare the results against a person or persons of interest and calculate a statistic, or “likelihood ratio,” of the strength of the match.
To date, STRmix™ has been used successfully in numerous U.S. court cases – including 22 successful admissibility hearings – and about 100,000 cases internationally. “Most recently, STRmix™ was used to provide DNA evidence which led to the convictions of a Brooklyn, NY man accused of murdering his estranged wife and two Florida men accused in the fatal drive-by shooting of a toddler,” explains Martin Riegel, Chief Executive Officer of STRmix™ Ltd., the newly formed subsidiary of ESR.
According to Riegel, a new version of STRmix™, containing a completely redeveloped and refreshed user interface, is scheduled for release later this year. The last version of STRmix™ to be introduced, STRmix™ v2.5, was launched in mid-2017 and featured improved functionality, speed, memory, and ease-of-use, including multi-kit functionality and a likelihood ratio (LR) batcher tool.
“I expect STRmix™ will continue adding new features and functionality as its use in criminal cases continues to grow and new applications come into play,” Riegel concludes.
For more information about STRmix™ visit http://www.esr.cri.nz/ or http://strmix.esr.cri.nz/.