Gilgo Beach killings: DNA evidence to be allowed in murder trial of Rex Heuermann, a precedent-setting decision for NYS courts

Hair DNA evidence Suffolk prosecutors say links alleged Gilgo Beach serial killer Rex A. Heuermann to the killings of six women will be admitted as evidence at a future trial, a Long Island judge ruled Wednesday in a precedent-setting decision.

"We won; the evidence is admissible," Suffolk District Attorney Ray Tierney said after a brief court conference in Riverhead.

State Supreme Court Justice Timothy Mazzei in Riverhead ruled cutting-edge DNA analysis using Astrea Forensics’ IBDGem software and whole genome sequencing method on nine hairs found with the remains of six of the victims will be admitted as evidence — a major victory for the prosecution.

Mazzei, in a 29-page ruling, said the two witnesses the defense put on the stand during a hearing on the DNA admissibility failed to provide to the court "empirical proof to refute the validated empirical evidence" presented by Richard Green, a co-founder of Astrea, who testified for the prosecution.

“While IBDGem is a relatively new software system, the principles used within it, which are behind the math used and data collected, are accepted as reliable in the scientific community based on the numerous peer review articles," Mazzei wrote.

Heuermann's lead defense attorney, Michael J. Brown, said his client is "disappointed" with the decision.

"We disagree with the court’s decision," said Brown, speaking to reporters outside the courthouse. "We think that the evidence is clear that they did not sustain their burden and it’s general acceptance in the relevant scientific community."

Brown said the DNA results, if allowed to stay after the court considers the defense motion claiming the testing is a violation of the state health law, will be further litigated at trial.

'Difficult subject'

Heuermann’s ex-wife, Asa Ellerup, attended Wednesday’s conference with her attorney, Robert Macedonio, who said in a statement after, "We are in the process of reviewing the court’s decision. We will have further comment upon review."

Before the conference began, Mazzei complimented prosecutor Andrew Lee and Heuermann defense attorney Danielle Coysh on the briefs they submitted to the court in support of their opposing stances on the DNA issue.

"Your briefs, albeit not brief, were truly excellent," Mazzei said. "The hearing told me that you really, really understand this difficult subject, and I appreciate that."

Tierney, speaking afterward in front of a bank of cameras, said he agreed "with the court’s kind words," adding the DNA issue was "very aggressively and effectively litigated by both sides."

"I think the reason why we were able to prevail, one simple reason: The science was on our side. And that’s why we won," he added.

Tierney also noted the historic nature of the ruling, allowing the DNA analysis to be presented in a New York court for the first time, that could allow for the same type of DNA analysis to be used in other cases across the state. He called the DNA, along with other prosecution evidence, "very compelling." 

"This decision and this litigation marks a significant step in forensic DNA analysis," said Tierney, adding of the technology: "That is a very discriminating and exact technique. And again, it just mirrors all the other fields, forensic fields and scientific fields, that use this evidence. So I think the criminal justice field just caught up today."

Several of the victims' family members — including Maureen Brainard-Barnes' mother, daughter and sister and Jessica Taylor's cousin — attended the conference and stood with Tierney as he spoke, but Tierney said they didn't want to comment. 

"I think they're feeling relieved and they're happy and pleased with the decision," Tierney said. 

No plea deal talks

Tierney appeared to close the book, at least for the meantime, on Heuermann facing charges in connection with any other killings, when he responded "no" to a reporter who asked if another superseding indictment against Heuermann could be expected. He was not asked about a potential separate indictment. 

Tierney also said there’s been no plea deal talks with Heuermann’s legal team.

"There’s only one person who makes that decision and I don’t have access to that person," Tierney said, referencing Heuermann and a potential deal for Heuermann to plead guilty. "So I’m in the dark, really, as much as you guys."

Asked about the possibility of his client pleading guilty, Brown said: "We are preparing for trial ... Switching his plea is not even a thought at this point."

Heuermann, a Massapequa Park architect who has been incarcerated at the Suffolk County jail in Riverhead since his July 14, 2023, arrest, has pleaded not guilty to multiple counts of first- and second-degree murder in the seven killings of women who authorities said were sex workers.

Immediately following the judge's ruling Wednesday, the defense filed a motion  arguing the work done by the lab, which is unaccredited, was in violation of New York State public health law. Defense attorney Sabato Caponi argued labs lacking state Health Department permits are prohibited from accepting specimens, and the DNA evidence should therefore not be allowed at trial.

"Any analysis performed by Astrea Forensics is unlawful and must be deemed presumptively unreliable," Caponi wrote in the motion. "To hold otherwise would be to ignore and render meaningless the plain unequivocal provisions of the New York State Public Health Law."

Mazzei ordered prosecutors to respond in writing to the motion by Sept. 22, and said he would rule on it, along with the defense motion for a severance, the following day. 

Tierney dismissed the motion’s argument when asked for a reaction and said his office had the DNA analysis conducted through the FBI, which maintains national standards on DNA testing.

"I said, If I was running a blood bank, I’d be very nervous, but since I’m not, I’m not nervous at all," Tierney said.

Several indictments

Heuermann was initially indicted on murder charges in the killings of Megan Waterman, Melissa Barthelemy and Amber Lynn Costello, who were each killed between 2009 and 2010.

Heuermann was then arraigned on a superseding indictment in January 2024 that charged him in the death of Brainard-Barnes in 2007. 

A second superseding indictment in June 2024 charged Heuermann with second-degree murder in the killing of Taylor in 2003 and Sandra Costilla, whose body was discovered in the Southampton hamlet of North Sea in 1993. Last December, Heuermann was indicted in the killing of New Jersey resident Valerie Mack in 2000.

Joann Mack, the mother of victim Valerie Mack, said she was satisfied with the judge's ruling.

"Very pleased, very pleased, this is the result we hoped for and are very happy about," she said.

While Ellerup divorced Heuermann, apparently to protect their marital assets, she publicly stood behind him, saying she didn’t believe he was guilty of the charges. But his adult daughter, Victoria Heuermann, in a Peacock documentary for which the family was paid over $1 million to participate in, said she thought her father had "most likely" committing the killings.

Prosecutors had said they linked Heuermann to the killings through DNA derived from hairs found with the remains of six of the seven victims. Heuermann’s defense had tried to have the DNA evidence thrown out, arguing the new technology and statistical analysis used to extract DNA from a rootless hair was not a widely accepted method in the scientific community, and therefore did not meet the legal threshold for admission into New York courts.

Won't seek change of venue

Brown said the defense has decided not to seek a venue change for Heuermann's trial, and hinted it would benefit the defense's case to have a jury that is familiar with the not-so-ancient history of corruption in the county's police department and district attorney's office. 

Both former Police Chief James Burke and District Attorney Thomas Spota served federal prison time for covering up the beating of a handcuffed prisoner, a scandal that left a black eye on Suffolk law enforcement.

"After we considered it and thought about it, we took it off the table because we have confidence in the folks in this county to listen to the evidence. They know the history of what has transpired in this county. We believe there is no better group of people to sit in judgment in this case." 

Newsday's Anthony M. DeStefano contributed to this story.