State Judge to Rule on Admissibility of Advanced DNA Evidence in Gilgo Beach Serial Killer Trial

RIVERHEAD, N.Y.-A pivotal hearing is set for Wednesday in Riverhead Supreme Court to determine whether groundbreaking DNA evidence may be introduced in the trial of accused Gilgo Beach serial killer Rex Heuermann, 61. Prosecutors seek to admit whole-genome sequencing results from a private lab, while the defense contends the methods remain unvalidated and potentially prejudicial.

Prosecutors have presented data from Astrea Forensics, a California laboratory that reconstructed genetic profiles from highly degraded hair samples recovered near Gilgo Beach, linking the strand found with victim Maureen Brainard-Barnes’ remains to Heuermann’s wife. The Suffolk County District Attorney’s office argues the sequencing provides “overwhelming” evidence of Heuermann’s guilt and represents a significant advancement in forensic science. Astrea’s co-founder testified that similar techniques have been accepted in other contexts, including a 2024 cold-case murder conviction in Idaho.

Defense attorneys have challenged the statistical models used by Astrea, asserting the lab’s likelihood calculations exaggerate match probabilities. They argue that the methods have not undergone sufficient peer review or gained broad acceptance in the scientific community. Experts called by the defense warned that allowing the evidence could “dramatically reshape” the admissibility standards for DNA in criminal trials.

Outside experts remain divided. William Thompson, emeritus criminology professor at the University of California, Irvine, echoed the defense’s call for more validation, describing the statistical approach as “unvalidated” with potential for unfair prejudice. In contrast, Manhattan’s John Jay College biology professor Nathan Lents contended that concerns are limited to mathematical nuances and do not undermine the laboratory process itself.

Prosecutors also maintain they possess corroborating evidence, including traditional DNA testing by a separate lab, cellphone records showing Heuermann’s proximity to multiple victims, and digital “blueprints” discovered on his computer outlining plans to commit and conceal the murders.

New York State Supreme Court Justice Timothy Mazzei will decide whether to admit the advanced DNA results into evidence. A ruling in favor of the prosecution could set a landmark precedent for the use of whole-genome sequencing in criminal courts nationwide, while a defense victory may slow the integration of such methods in legal proceedings.