Gilgo Beach killings: Murder case against accused serial killer Rex Heuermann is ready for trial, court paper says

The Suffolk County District Attorney's Office declared Wednesday that it has completed its obligations to turn over evidence to the defense and is ready for trial in the case against alleged Gilgo Beach serial killer Rex A. Heuermann, marking a pivotal moment in the decades-old case.

Prosecutors on Wednesday turned over to the defense a final computer drive that included a 723-page master inventory of evidence in the case and a list of more than 7,000 people, both law enforcement and civilians, who "may have evidence or information relevant" to the charges or potential defense, according to the certificate of compliance filed with the court. The disclosure also contains a list of expert witnesses who may be called at trial, the filing states.

"The people further announce ... that we are ready for trial," reads the statement of readiness filed by Assistant District Attorney Michelle Haddad.

The defense now has 30 days to respond to discovery obligations under New York State law. Defense attorney Michael J. Brown, of Central Islip, previously said he intended to file additional pretrial motions once the prosecution certified its case.

The defense also has two pending motions State Supreme Court Justice Timothy P. Mazzei is expected to rule on next week, including one prosecutors responded to in a filing made public Wednesday morning.

Suffolk Assistant District Attorney Andrew Lee argued a second effort by the defense to suppress nuclear DNA evidence linking him to the Gilgo Beach killings should be rejected because the law cited in defense arguments does not apply to criminal proceedings, the court records show.

The Heuermann defense team had argued the DNA evidence deemed admissible Sept. 3 was gathered in violation of state Public Health Law since the laboratory conducting the testing lacked New York State Department of Health permits. 

Lee dismissed the defense motion as an "11th-hour attempt" to suppress evidence already deemed admissible through a "strained and selective reading" of the law. Lee argued the public health law only governs the identification of "disease, medical conditions and paternity" and does not pertain to "criminal identifications."

"The statute is self-limiting to matters of public health and does not extend to criminal proceedings," Lee wrote in his response.

Heuermann, a Massapequa Park architect with offices in Manhattan, has been charged with killing seven women who authorities said worked as escorts. He has pleaded not guilty to the charges.

Mazzei said he will rule on the motion, and on a defense request to host separate trials for some of the seven alleged killings, when Heuermann returns to court Sept. 23. The judge also indicated he could set a tentative trial date at that time.

The district attorney’s office gave several additional reasons for why the defense’s latest motion to suppress DNA evidence must be rejected, including that the arguments should have been raised during the prior admissibility hearings.

"The defendant is not merely late, he is attempting to relitigate an issue that has already been decided," Lee wrote.

Mazzei ruled Sept. 3 that cutting-edge DNA analysis using Astrea Forensics’ IBDGem software and whole genome sequencing method on nine rootless hairs found with the remains of six of the victims will be admitted as evidence.

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.

In his ruling, the judge 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.

Brown said regardless of the judge’s decision, the DNA evidence will be further litigated at trial.

Heuermann, who turned 62 Saturday, was arrested in July 2023 on an indictment charging him with murder 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 Maureen Brainard-Barnes in 2007. The remains of the four women were all found near Gilgo Beach in December 2010.

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

Partial remains of Taylor and Mack were found at both Gilgo Beach and in Manorville. Costilla's body was discovered shortly after her death in the Southampton hamlet of North Sea.

Heuermann is awaiting trial at a county jail in Riverhead since his arrest in 2023.

By Grant Parpan

grant.parpan@newsday.com@GrantParpan

Grant Parpan covers Suffolk County courts and federal courts for Newsday. A Long Island native, he joined Newsday in 2022.