Florida Circuit Court Rules DNA Evidence Produced by STRmix™ Analysis Is Admissible in First-Degree Murder Case

A Florida Circuit Court has ruled that evidence produced through the use of STRmix™ – the sophisticated forensic software used to resolve mixed DNA profiles previously thought to be too complex to interpret – is admissible in Florida v. Reshaunte Jermaines Anglin (Case No. 2017-CF-7816-XX, Section F9), a 2016 case in which the defendant is charged with first-degree murder, robbery with a firearm, and evidence tampering.


Denying a defense motion to exclude opinion evidence, Judge Jalal A. Harb of the Tenth Judicial Circuit Court for Polk County, FL, ruled, “The unrefuted testimony [of Senior DNA Analyst Cristina Rentas, who tested the DNA samples in the case] supports that the STRmix™ analysis has been sufficiently tested and accepted in the scientific community for DNA forensics.”


Judge Harb continued, “The basic underlying principles [of STRmix™] are merely an evolution of well-established DNA testing. STRmix™ utilizes this existing DNA science to provide a probabilistic ratio. The mathematics from which this is derived dates back to at least the 1980s, with over three million scholarly articles on the subject.”


Judge Harb concluded that the DNA analysis produced by STRmix™ was admissible under both the Frye and Daubert standards – the two legal metrics used to assess the validity of scientific techniques or methods.


The Frye standard requires that a new or novel scientific technique be generally accepted in the relevant scientific community, and that the particular evidence derived from the technique and used in an individual case has a foundation that is scientifically reliable.


The Daubert standard is used to assess whether an expert’s scientific testimony is based on reasoning or methodology that is scientifically valid and can properly be applied to the facts at issue. Factors considered in determining the validity of a methodology include whether it has been subjected to rigorous testing and validation, published and peer reviewed, and generally accepted in the scientific community, as well as in federal and state courts throughout the U.S.


To date, there have been at least two dozen successful admissibility hearings for STRmix™ in the U.S., while DNA evidence interpreted with STRmix™ has been successfully used in numerous court cases.


Forty U.S. forensic labs now routinely use STRmix™ to resolve DNA profiles, including the FBI, the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF), and multiple state and local agencies. STRmix™ is also in various stages of installation, validation, and training in more than 50 other U.S. labs.


Internationally, STRmix™ has been used in casework since 2012. Currently in use in 14 labs in Australia, New Zealand, England, Scotland, Ireland, and Canada, STRmix™ has been used to interpret DNA evidence in more than 100,000 cases.


A new version of STRmix™, STRmix™ v2.6, was introduced in August 2018. The new version features a user interface that has been completely redeveloped and refreshed, providing users with vastly improved usability and workflow. Version 2.6 also enables a range of contributors to be entered when performing a deconvolution, and any type of stutter to be added and configured.


STRmix™ was developed by John Buckleton, DSc, FRSNZ, and Jo-Anne Bright of the New Zealand Institute of Environmental Science and Research (ESR), and Duncan Taylor from Forensic Science South Australia (FSSA).


For more information about STRmix™ visit www.strmix.com.