Suspected Gilgo Beach killer Rex Heuermann contacted sex workers hundreds of times, viewed sadistic killings of women online, DA says

Accused Gilgo Beach serial killer Rex A. Heuermann contacted at least 60 sex workers more than 500 times in the four years leading up to his 2023 arrest, prosecutors alleged in a Tuesday court filing that provides the most detailed account of the case against the Massapequa Park resident to date.

The district attorney's filing also reveals that investigators found Heuermann had searched for images of family members of alleged victims "mourning the deceased" before his arrest. Other searches made under an email account tied to one of Heuermann’s cellphones include attempts to access pornographic "snuff" films depicting murder and "bruised and impaled women," the court records show.

A Suffolk police detective concluded that more than a thousand Heuermann searches reviewed by investigators established there was "clear evidence" he was a "sexual sadist" receiving pleasure from the physical and psychological pain of others, according to the motion.

Prosecutors, who have long said Heuermann’s persistent contact with sex workers played a role in the timing of his July 13, 2023, arrest, also disclosed in the new court records that Heuermann was making recurring payments to the online dating app Tinder.

Heuermann’s "modern day use of burner phones to patronize prostitutes is probative ... of [his] modus operandi," Assistant Suffolk County District Attorney Andrew Lee wrote in the motion filed Tuesday.

Court imposed deadline

The filing comes as prosecutors faced a court-imposed deadline to respond to a defense motion seeking to suppress evidence at trial, including search warrants used to obtain cellphone and email data for accounts Heuermann allegedly created in the years after his alleged crimes. Heuermann, 62, of Massapequa Park, is set to stand trial in September for seven killings he is alleged to have committed between 1993 and 2010.

Prosecutors focused heavily on two phones in the filing, one of which they previously disclosed was in Heuermann’s possession at the time of his arrest, which they say he registered under aliases and used almost exclusively to contact sex workers. One phone they allege was used to contact numbers associated with 56 sex workers and massage parlors over 300 times between January 2021 and March 2022. Another phone the Manhattan architect allegedly kept active until February 2023 made contact with 61 "prostitution-related" numbers more than 220 times before his arrest. Evidence obtained from search warrants show those phones were kept near a phone registered in Heuermann’s actual name at all relevant times, the filing reveals.

Lead Heuermann defense attorney Michael J. Brown, of Central Islip, said he had not yet had an opportunity to fully review the district attorney’s response — which was submitted to the court minutes before the close of business Tuesday — and he declined to comment late Tuesday night.

Prosecutors ultimately argued that State Supreme Court Justice Timothy Mazzei should deny all nine suppression requests Heuermann made in a Jan. 13 filing.

His "motion is premised upon a selective characterization of the record that does not fully reflect the evidence," Lee concluded. "When the facts are considered in their entirety and in their proper context, there is no legal or factual basis to grant the relief requested by the defendant."

If any hearing should be granted, prosecutors argued, it should be limited to the admissibility of prior uncharged acts they may seek to introduce at trial.

Charge dismissal request

One of the relief requests made by the defense includes asking the judge to dismiss a second-degree murder count charging Heuermann in the 1993 killing of Sandra Costilla in North Sea. Prosecutors argue that Heuermann’s contention that the grand jury presentation regarding Costilla was insufficient is without merit and relies on "an exaggerated characterization of the facts."

Prosecutors say the grand jury was presented with DNA evidence linking both Heuermann and his ex-wife to hair found at the Costilla crime scene and was aware of evidence that Heuermann kept mementos from all of his killings.

"The grand jury could have rationally drawn the inference that defendant’s possession of the 31-year-old Nov. 22, 1993 edition of Newsday, in pristine condition, was no coincidence, but a pattern that points to defendant possessing these publications as souvenirs or mementos of his crimes, serving as a reminder of the events that occurred throughout the murders of each victim," Lee wrote.

Prosecutors also contend that by arguing investigators violated privacy laws when they obtained DNA evidence linking Heuermann to the crime scene through a discarded pizza box and drink bottles, that the defense is conceding Heuermann was the contributor of those samples, which later matched a court-ordered swab of the accused killer.

Prosecutors also urged Mazzei to shoot down a request made by Heuermann’s defense to obtain potential statements made with immunity by former Suffolk County Police Chief James Burke, whom they intend to introduce as an alternative suspect at trial. While prosecutors do not deny that such an agreement exists following his 2023 misdemeanor arrest for indecent exposure, they argue the case has no relevance to the prosecution of Heuermann.

Hundreds of thousands of discovery pages

Prosecutors have to date turned over 630 pages of discovery related to Burke, who was also previously convicted in a federal corruption case, to the Heuermann defense, the filing shows.

To date Heuermann has received 715,000 pages of discovery in the case, including 65,000 pages related to investigations of other persons of interest in the alleged killings and more than 33,000 pages of potential leads called in by members of the public, the prosecution’s reply reveals.

Prosecutors say they have also provided the defense with a 99-page list of potential civilian witnesses, and a 48-page list of law enforcement and five-page list of experts witnesses who could be called to testify. Prosecutors do not intend to introduce any statements Heuermann made to police following his arrest, dismissing them as self-serving, the court records show.

The defense to date has not turned over any discovery, prosecutors noted, urging Mazzei to order them to do so within 60 days of his ruling on the suppression motions. The judge previously said he intends to rule on the remaining issues when Heuermann returns to court March 17.

Heuermann was first indicted in July 2023 on first-and second-degree murder charges in the killings of Melissa Barthelemy, Amber Lynn Costello and Megan Waterman, who were killed between 2009 and 2010. He was later indicted for second-degree murder in the 2007 killing of Maureen Brainard-Barnes, Jessica Taylor in 2003, Valerie Mack in 2000 and Costilla in 1993. He has denied any involvement in the killings and has pleaded not guilty to all 10 charges.

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.