Gilgo Beach killings: Alleged serial killer Rex Heuermann back in court for judge's ruling on hair DNA evidence
Alleged Gilgo Beach serial killer Rex A. Heuermann is escorted into a hearing at Suffolk County Court in Riverhead on July 17. Credit: Newsday/James Carbone
Rex A. Heuermann, the alleged Gilgo Beach serial killer who is charged with killing seven young women, is slated to return to a Riverhead courtroom Wednesday, where he will learn whether DNA evidence that prosecutors say links him to the killings of six of the seven victims will be admitted as evidence at his future trial.
In a decision that will be pivotal in Heuermann’s case and would be precedent-setting in the New York State court system, State Supreme Court Justice Timothy Mazzei is scheduled to rule on whether the DNA analysis using Astrea Forensics’ IBD Gem software and whole genome sequencing method will be admitted as evidence. The methods have never been used as evidence in New York courts.
Heuermann, 61, the Massapequa Park architect who prosecutors said targeted sex workers and killed them while his family was away on vacation, has contested the charges and vowed, through his attorneys, to fight them at trial.
Prosecutors have said that the California lab connected Heuermann, his ex-wife, Asa Ellerup, and their adult daughter, Victoria Heuermann, to hair strands found on the remains of six of the seven victims. Prosecutors have said that Heuermann committed the killings while his wife and children were out of state or traveling internationally.
Expert witnesses for both the prosecution and defense testified during a Frye hearing that took place for several days over months, in an effort to inform the judge’s ruling. The Frye standard of admissibility dictates that a scientific method must be generally accepted in order for it to be allowed to be presented before a jury in a New York court.
The defense has argued that the whole genome sequencing method and probabilistic genotyping to create likelihood ratios used by California-based Astrea Forensics and its IBDGem software — used to link Heuermann to degraded rootless hair samples found at the Gilgo Beach crime scenes — is not widely used.
The defense attacked the accuracy of IBDGem, which compares the evidence sample DNA to an open-source repository of about 2,500 human genomes called the 1,000 Genomes Project. Dan Krane, a professor of biological sciences at Wright State University in Ohio and the president and CEO of Forensic Bioinformatic Services, testified that the DNA analysis is a shift away from established methods.
Heuermann defense attorney Danielle Coysh, in a brief to the court, questioned the whole genome sequencing performed on rootless hairs and other degraded samples and said the methods had only been used in one other criminal case — in Idaho.
But Kelly Harris, a population geneticist who testified for the prosecution, said the nuclear DNA techniques and likelihood ratios linking degraded hair samples found at the Gilgo Beach crime scenes to Heuermann are "widely accepted" in the scientific community.
"It's embarrassing for our criminal justice system that a method like this wasn't the state of the art years ago," Harris said, Newsday previously reported.
Prosecutor Andrew Lee, in his response brief to the court, argued that the whole genome sequencing method has been adopted in related fields such as human identification and disease genetics. Plus, Lee argued, New York has often been on the forefront of investigative techniques like cellphone tracking that has become standard in law enforcement.
Prosecutors have also argued that the DNA results linking Heuermann to the crimes were corroborated by a second lab's DNA analysis.
Heuermann, who was arrested on July 13, 2023, outside his architecture firm in midtown Manhattan after the crimes went unsolved for decades, has pleaded not guilty to the killings of seven women from 1993 to 2010.
The victims are: Melissa Barthelemy, Megan Waterman and Amber Lynn Costello, Maureen Brainard-Barnes, Jessica Taylor, Sandra Costilla and Valerie Mack.
The presiding judge has yet to rule on a defense request seeking to separate the cases into more than one trial.
Nicole Fuller is Newsday's senior criminal justice reporter. She began working at Newsday in 2012 and previously covered local government.
