The Houston Forensic Science Center (HFSC) and Northeastern Illinois Regional Crime Laboratory (NIRCL) are the latest U.S. forensic labs to announce plans to use STRmix™ to resolve DNA profiles in criminal investigations.
Developed in New Zealand and South Australia, STRmix™ is sophisticated forensic software that can be used to resolve mixed DNA profiles previously thought to be too complex to interpret.
HFSC examines and provides scientific analysis of evidence for the Houston Police Department (HPD). The Center manages HPD’s Crime Laboratory and Crime Scene Unit, as well as parts of its Identification Division.
NIRCL provides forensic services to 57 member law enforcement agencies which govern and fund its operations. NIRCL provides accurate, objective, and timely forensic services for Chicago’s suburbs and collar communities, serving an estimated population of approximately 1.6 million citizens.
With the addition of the two new forensic labs, a total of 48 U.S. labs now regularly use STRmix™. Other labs announcing plans to use STRmix™ in just the past year include the Nebraska State Patrol, the University of Nebraska Medical Center Human DNA Identification Laboratory, the Massachusetts State Police Crime Laboratory, Orange County (CA) Crime Laboratory, and Los Angeles Police Department Forensic Science Division.
Those labs join a national list of labs that includes the FBI and the Federal Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF). STRmix™ is also in various stages of installation, validation, and training in more than 60 other U.S. labs.
“Forensic labs are turning to STRmix™ because it has greatly improved their ability to produce usable DNA evidence in a wide range of criminal cases,” says John Buckleton DSc, FRSNZ, Forensic Scientist at the New Zealand Institute of Environmental Science and Research (ESR) and one of the developers of STRmix™.
According to Dr. Buckleton, agencies using STRmix™ are reporting an increase of interpretable DNA in gun cases from about 40% to more than 70%. STRmix™ is also proving to be highly effective in sexual assault cases.
“Given the considerable resources invested in both resources and staff time to clear Sexual Assault Kit backlogs, forensic labs are quickly recognizing that STRmix™ is producing a much better return on investment by delivering a significantly higher rate of interpretable results,” Dr. Buckleton explains.
Since its introduction in 2012, STRmix™ has been used to interpret DNA evidence in more than 120,000 cases around the world. It has also been used successfully in numerous U.S. court cases, including 28 successful admissibility hearings.
A new version of STRmix™, STRmix™ v2.7, was introduced in September. STRmix™ v2.7 includes several new features in direct response to recommendations for improvements made by forensic labs to better address the on-the-job needs they regularly encounter. DBLR™, an application used with STRmix™, was also introduced earlier this year. DBLR™ allows users to undertake superfast database searches, visualise the value of their DNA mixture evidence and carry out mixture to mixture matches.
In addition, an updated STRmix™ Defense Access Policy gives defense legal teams even easier access to STRmix™ software. The updated Access Policy includes definitions of the extended items that can be provided under the policy, updated non-disclosure agreements (NDAs), and an abbreviated NDA for use in some specific circumstances.