In a stunning courtroom twist that closed a 31-year chapter of unsolved violence, convicted serial killer Rex Heuermann has pleaded guilty to the murder of eight women, including 28-year-old Trinidadian native Sandra Costilla, in a Suffolk County, New York court. The 62-year-old Manhattan architect, a married father of two who hid a brutal double life as a predatory killer for three decades, entered the guilty plea this week, reversing his earlier not guilty plea entered ahead of his scheduled September 2024 trial.
Heuermann, who stood 6-foot-4, began his killing spree as early as 1993, when Costilla – a migrant who had moved to the U.S. from Trinidad and Tobago at age 17 and was living in Queens at the time – became his earliest known victim. On November 20, 1993, two hunters discovered her body on New York’s Long Island in the North Sea area. Court documents detail extensive, brutal injuries: multiple sharp-force wounds to her face, torso, breasts, left thigh, and vaginal region, with her body positioned in a degrading arrangement. Heuermann confirmed in court this week that he strangled Costilla to death, the same method he used to kill all eight of his confirmed victims. He pleaded guilty to three counts of first-degree murder and four counts of second-degree murder, which includes Costilla’s killing.
For three decades, Costilla’s case remained unsolved, until advances in forensic DNA testing connected cold case evidence to Heuermann, who was first arrested in 2023 in connection with the long-running Gilgo Beach serial killings. During the initial 1993 investigation of Costilla’s death, forensic analysts from the Suffolk County Crime Lab recovered three hair strands from her body and clothing: one from her right arm, one from a striped shirt found near her body, and a third from a white shirt. DNA testing at the time confirmed one hair came from a male suspect, and the other two from female contributors. Decades later, the Gilgo Beach Homicide Task Force retested the evidence, and in February 2024, forensic results confirmed the male hair from Costilla’s striped shirt matched Heuermann’s DNA. One of the two female hairs was even traced to a woman who lived with Heuermann shortly before Costilla’s 1993 murder, cementing the connection between the killer and the decades-old crime.
Courtroom observers reported Heuermann spoke in a calm, matter-of-fact tone about his crimes, confirming that he dismembered some victims and bound others by the head and legs. Investigators who seized 422 electronic devices from Heuermann’s home uncovered disturbing evidence that prefigured his crimes: a handwritten planning document that noted “SMALL IS GOOD” – a reference to the fact that all eight of his known victims, including Costilla, were petite women. Another entry in the planning document read: “HIT HARDER TOO MANY HIT TO TAKE DOWN. CONSIDER A HIT TO THE FACE OR NECK NEXT TIME FOR TAKE DOWN.”
Investigators also found a massive, decades-spanning collection of violent, bondage, and torture pornography on his devices, dating back to 1994. The content includes graphic depictions of breast mutilation, sexualized violence against women, bondage, and whipping – imagery that aligns closely with the injuries found on Costilla and two other victims. Unlike many of Heuermann’s later victims, who were sex workers, investigators have found no evidence Costilla worked in the sex trade. Unlike his later crimes, which relied on disposable burner phones to contact victims, the 1993 killing of Costilla predates widespread consumer cell phone use and social media, leaving investigators still unclear on how Heuermann first encountered his earliest victim. Heuermann is scheduled to receive his formal sentence on June 17, 2024.