The first witness called by the defense of accused Gilgo Beach killer Rex Heuermann said Astrea Labs lacked the proper validation and verification framework for their samples, adding that the labs “test plans, records and result of testing don’t exist”
Nathaniel Adams, a systems engineer at Forensic Bioinformatic Services, a company that reviews cases involving forensic DNA testing in Fairborn, Ohio, testified that the California-based forensic lab failed to follow some 21 nationally accepted verification and validation standards to ensure the software was performing accurately.
"It's unreliable," he said to Heuermann's defense attorney Danielle Coysh in front of state Supreme Court Justice Timothy Mazzei in Suffolk County Court on June 17.
Adams was the fourth witness called in the case’s Frye hearing. The legal proceeding, also known as a general acceptance hearing, is used to determine that scientific evidence presented in court is widely accepted and considered valid within the relevant scientific community.
The systems engineer mentioned that he has testified about DNA analysis and software in trials and pre-trails at both the state and federal level during his testimony. In all 30 cases he testified in, he did it on behalf of the defense, Adams added.
Suffolk County District Attorney Ray Tierney focused on Adam’s experience and credentials, arguing that the systems engineer lacked the necessary knowledge to criticize Astrea and its probabilistic genotyping software.
After a full day of testimony, Adams is set to return to court on June 18. The defense is expected to call at least one more witness in July, while the prosecution formally rested its case the morning before Adams testified.
Both Tierny and Michael Brown, Huermann’s court-appointed lawyer, declined to speak with the media after the proceedings. “See you tomorrow,” Tierny said while walking out of the courtroom after the hearing had finished.
Heuermann, a 61-year-old who lives in Massapequa Park, now stands charged with the murders of seven people in total: Melissa Barthelemy, Maureen Brainard-Barnes, Amber Lynn Costello, Megan Waterman, Jessica Taylor, Sandra Costilla, and Valerie Mack. He has pleaded not guilty to all charges and has maintained his innocence since his arrest.
Prosecutors have said Astrea Forensics linked him to six of the seven killings through the testing of rootless hair found at the crime scenes and comparative analysis of those hairs to DNA samples obtained by Heuermann and family members.
Heuermann’s defense has called for those tests to be excluded from the trial, saying the California-based lab’s method has never been accepted in a New York court of law.
No trial date has been set for the case, which spans decades of killings on Long Island and has been the subject of national interest.
