(NewsNation) — A judge has ruled that DNA evidence gathered through advanced testing called genome sequencing can be used against Rex Heuermann at trial.
Judge Tim Mazzei’s ruling is significant in the case against the alleged Gilgo Beach serial killer, Suffolk District Attorney Ray Tierney told “Elizabeth Vargas Reports” Wednesday.
Prosecutors say the evidence links Heuermann to six of the seven murders he’s accused of committing from 1993 to 2011.
The judge’s decision to allow the evidence at trial marks the first time DNA evidence generated through whole genome sequencing has been admitted in a New York court.
It’s also one of just a handful of such instances nationwide, according to prosecutors, defense lawyers and experts.
“For criminal forensics in the court, it’s new, but the forensics in our courtrooms have been lagging behind our science,” Tierney said.
“Because when you talk about anthropology, when you talk about medical science, when you talk about gene therapy, identification of war dead and the like, this technology has been around for decades, so this is just a new application of an old science.”
What is whole genome sequencing?
About seven years ago, investigators turned to Astrea Forensics, a California lab using new techniques to analyze old, highly-degraded DNA samples.
The firm examined hairs recovered from six victims: Maureen Brainard-Barnes, Megan Waterman, Amber Costello, Sandra Costilla, Jessica Taylor and Valerie Mack.
Whole genome sequencing was used to extract DNA from the hairs. A profile was then created and compared to Heuermann’s DNA profile.
Prior to the ruling, Heuermann’s lawyers argued that Astrea’s DNA methods hadn’t been subjected to enough scrutiny, and warned they needed more evaluation because they had the potential to “dramatically reshape” how forensics is used in criminal trials.
But Judge Mazzei sided with prosecutors, ruling that nuclear DNA results obtained from rootless hairs are admissible at trial.
Heuermann was arrested in July 2023 and has pleaded not guilty to all the charges against him.
The Associated Press contributed to this report.