Rex Heuermann Expected to Plead Guilty in Gilgo Beach Serial Killings

Rex Heuermann, a former architect charged with murdering seven women over 17 years, is set to change his plea from not guilty at his next scheduled court hearing on April 8, bringing a case that has haunted Long Island for more than three decades to what would be an extraordinary close in a Riverhead courtroom.

The families of Heuermann's alleged victims, as well as his own family, have been notified of the decision to change his plea, according to a source familiar with the case. Any guilty plea would still have to be accepted by a judge. Suffolk County District Attorney Ray Tierney declined to comment, and lawyers for Heuermann did not respond to requests for comment.

The victims connected to the case include Melissa Barthelemy, Maureen Brainard-Barnes, Amber Lynn Costello, Sandra Costilla, Valerie Mack, Jessica Taylor and Megan Waterman. Their remains were found discarded on Long Island between 1993 and 2011; Sandra Costilla was the first, killed in 1993, followed by Valerie Mack in 2000 and Jessica Taylor in 2003. Maureen Brainard-Barnes was killed in 2007 and found near Gilgo Beach, while Megan Waterman, Melissa Barthelemy and Amber Lynn Costello were killed between 2009 and 2010 and also recovered near Gilgo Beach.

Heuermann, a Manhattan architect who lived on Long Island, was arrested on July 13, 2023 and initially charged in the murders of Amber Lynn Costello, Megan Waterman and Melissa Barthelemy. The charges expanded steadily over the following 18 months. In January 2024, he was charged in the death of Maureen Brainard-Barnes, and on June 6, 2024, he was arraigned on charges of murdering Jessica Taylor and Sandra Costilla, a case notable because Costilla's murder had not previously been linked to the Gilgo Beach killings. The December 17, 2024 indictment for Valerie Mack's murder completed the seven-count roster.

The investigation of a potential Long Island serial killer spilled into public view in 2010, when police searching for a missing woman discovered numerous sets of human remains in the scrub along Ocean Parkway, not far from Gilgo Beach. Over the years, investigators used DNA analysis and other clues to identify the victims, and in some cases were able to connect them to remains found elsewhere on Long Island years earlier. Detectives linked Heuermann to a pickup truck that a witness reported seeing when one of the victims disappeared in 2010, then recovered a pizza crust he had discarded in the trash and used it to link him to DNA from a hair recovered from one of the victims' bodies.

Last year, investigators recovered files from Heuermann's computer that they described as a "blueprint" for the killings, including a series of checklists with reminders to limit noise, clean the bodies and destroy evidence. The defense tried multiple times to exclude DNA evidence, arguing that evidence developed by Astrea Forensics violated state public health law because the California lab does not hold a required permit from New York's health department to handle lab specimens. The judge denied both attempts.

Bob Macedonio, lawyer for Heuermann's ex-wife Asa Ellerup and their daughter Victoria Heuermann, spoke to the weight of a potential plea last September outside Suffolk County Court in Riverhead. A guilty plea would "spare the seven victims' families of listening to the horrific nature of these allegations," Macedonio said, adding, "And you also have Rex Heuermann's family that could be spared of listening to these allegations. But that's a decision that would be made by Mr. Heuermann and Mr. Tierney's office."

Judge Timothy Mazzei, who presides over the case, had previously said he wanted the matter to go to trial right after Labor Day. If Heuermann follows through on April 8, that September courtroom will stay empty.