Gilgo Beach killings: Rex Heuermann expected to plead guilty to homicides in a case that has haunted Long Island for a decade

Family members of women whose remains were found near Gilgo Beach have been notified that alleged serial killer Rex A. Heuermann is expected to plead guilty next month, relatives told Newsday.

The Massapequa Park architect, accused of killing seven women in a case that has haunted Long Island for more than a decade, is expected to change his plea during a scheduled appearance April 8, the family members said. Details of the expected plea agreement have not been disclosed and the deal could still fall through for a range of reasons, including second thoughts by Heuermann and the prosecutor. The judge could also refuse to sign off.

Suffolk County District Attorney Ray Tierney and defense attorney Michael J. Brown declined to comment on the anticipated guilty plea when contacted by Newsday this week. 

Heuermann, 62, who owned a Manhattan architectural consulting business until his arrest in July 2023, has so far publicly denied any involvement in the killings. A trial had been expected for September. He faces life without parole if convicted of the top charge of first-degree murder.

Heuermann first became a suspect in the case, which involves at least two still-uncharged killings, in March 2022 after a New York State Police investigator with the Gilgo Beach Homicide Task Force learned while reviewing the case file that alleged victim Amber Lynn Costello was picked up by a man driving a green Chevrolet Avalanche. Police had already determined that the likely killer lived in Massapequa Park and worked in New York City based on phone calls placed to the victims from those locations.

"Rex Heuermann is a demon that walks among us, a predator that ruined families," then-Suffolk County Police Commissioner Rodney K. Harrison said at a news conference announcing Heuermann’s arrest.

To build the case, the task force — which consists of members of the Suffolk Police Department, New York State Police, FBI, Suffolk County Sheriff's Office and the Suffolk District Attorney's Office — tracked burner phones, triangulated cell site data, used advanced DNA testing on strands of hair found on the victims' bodies, surveilled Heuermann and picked up his DNA from a leftover pizza crust in a box he discarded in Manhattan, court papers show.

"For each of the murders, he got an individual burner phone and he used that to communicate with the victims and then shortly after the death of the victims, he then would get rid of the burner phone," Tierney said at the July 14, 2023, news conference.

Investigators also learned through his internet search history that Heuermann viewed torture pornography and maintained an active interest in the investigation, prosecutors revealed.

Heuermann was arrested while walking away from his Manhattan office on July 13, 2023, and arraigned on an initial indictment the following day even as the investigation into additional killings continued.

Police seized the opportunity to make the arrest then because investigators were concerned that Heuermann continued to use the services of sex workers and might attack again, prosecutors have alleged.

Heuermann was initially charged with first- and second-degree murder in the killings of Costello, Melissa Barthelemy and Megan Waterman. In January 2024, a special grand jury also indicted him on a second-degree murder charge in the death of Maureen Brainard-Barnes, effectively answering the question of who killed the "Gilgo Four," the first set of remains found off Ocean Parkway near Gilgo Beach in December 2010. The women, whose skeletal remains were all discovered without clothes and bound, were killed between 2007 and 2009, each at times when Heuermann stayed behind as his wife, Asa Ellerup, and children left for vacations, prosecutors have said.

Heuermann was indicted twice more in the more than two years he has spent in isolation at the Suffolk County Jail in Riverhead on three additional second-degree murder charges that widened both the geography and timeline of the alleged killings and exhibited a perceived shift in the way the accused killer carried out the crimes.

Alleged victims Valerie Mack, in 2000, and Jessica Taylor, in 2003, were both mutilated, their severed bodies dumped near each other off Ocean Parkway and 40 miles east in the vast woodlands of Manorville. Sandra Costilla was also discovered with sharp-forced wounds to her body even farther east in the Southampton Town hamlet of North Sea in 1993, about 60 miles from Gilgo Beach. Their bodies were all found within days of their disappearances, which prosecutors have also said occurred while Heuermann was alone in the Massapequa Park home he lived in with his family. The killings likely happened in the basement of the home, prosecutors have said.

All seven women were said to have engaged in sex work, officials have said.

Perhaps the strongest evidence linking Heuermann to the killings came in the form of nuclear and mitochondrial DNA analysis done by outside laboratories that linked him to six of the seven killings by showing it was highly likely individual hairs belonged to him, his wife, their daughter and, in the case of Costilla, a woman he was previously married to, prosecutors have said.

A search warrant at Heuermann’s home also revealed he once maintained an alleged planning document for how to best execute the killings and evade detection by law enforcement. Prosecutors asserted the file, which was deleted more than two decades ago but recovered through technology used by federal investigators, showed that in the years between the Mack and Taylor killings, Heuermann sought out smaller women, scouted dump sites, maintained a list of supplies useful to a killer and thought vigorously about ways to clean bodies and crime scenes. Under the plan, rooms should be soundproof and car tires should be changed after the disposing of bodies.

"Remember don’t charge gas," he allegedly wrote in the file.

But prosecutors still used financial documents as well as day planners he kept to build the case against him, as his defense team filed motions to have the DNA and other evidence suppressed. His April 8 appearance was scheduled for state Supreme Court Justice Timothy Mazzei to make a ruling on the latest defense motion.

The guilty plea would come at a time when even more of the public has become aware of the high-profile case, following the release of two multipart streaming documentary series featuring the families of the victims and Heuermann’s wife and daughter.

Melissa Cann, the sister of Brainard-Barnes, spoke with the filmmakers of a series that debuted on Netflix last March about how the families of the victims have been bonded by the way they lost their loved ones.

"I think us as families coming together is very important because you have people that are going through the same thing as you, that understand," Cann said in the series.

A separate documentary released on Hulu in July saw Heuermann’s own family trying to reconcile how he might have committed such a crime. A slide near the end of the third episode revealed Victoria Heuermann now believes her father "most likely" committed the killings. She described her feelings toward him as "love-hate" since his arrest.

"I love him as my dad," she tells the interviewer. "The hate is this other side of him that came out."

If Heuermann does change his plea April 8, Mazzei would then schedule sentencing for a later date.