Files Allege Rex Heuermann Contacted Hundreds of Sex Workers, Searched Disturbing Content

Prosecutors in Suffolk County filed new court papers in early March 2026 alleging Long Island architect Rex A. Heuermann contacted at least 60 sex workers repeatedly in the years before his July 14, 2023 arrest outside his Midtown Manhattan office, and disclosed internet search activity was included in the filing. The papers were submitted in Suffolk County Criminal Court in Riverhead, where Justice Timothy Mazzei is overseeing the multi-decade homicide prosecution.

Defense attorneys delivered a 178‑page filing on the eve of a Riverhead appearance that lays out what they say happened in Heuermann’s first 24 hours in custody and asks the court to exclude those statements at trial. The filing quotes arrest remarks the defense says were made involuntarily - “What is this about?,” “It's a mistake.,” and “What did I do?,” and attributes another line to Heuermann as officers reviewed his property: “I guess I won't be needing that.” Defense counsel Danielle Coysh argued those comments “were involuntarily made and may not be used in evidence against the defendant.”

The defense also moved to dismiss at least one count tied to a decades-old case, asking the court to drop the 1993 murder charge in the death of Sandra Costilla. Coysh challenged the forensic link prosecutors relied on, arguing that a hair recovered from Costilla’s shirt “does not establish that Mr. Heuermann killed Sandra Costilla, nor that he acted with the intent to cause her death,” and adding that “The prosecution presented no eyewitness testimony, surveillance footage, digital evidence, phone records, fingerprint impressions, confession, or murder weapon linking Rex A. Heuermann to this crime.” Justice Mazzei set a deadline for the District Attorney’s Office to respond by March 3 and scheduled Heuermann’s next appearance for March 17.

Searches of Heuermann’s home yielded what investigators described as a trove of evidence, including 46 cell phones, a collection of violent bondage pornography, and a Microsoft Word document prosecutors say planned the crimes “in excruciating detail.” Suffolk County District Attorney Raymond Tierney told investigators, “I’ve never seen a written document such as this.” In a bail application prosecutors wrote, “Defendant Heuermann is the individual who murdered, stripped, restrained, and transported the remains of Jessica Taylor and Sandra Costilla, as well as the Gilgo Four, until they were each discovered in 1993, 2003, 2010, and 2011.”

Victims named in the charging materials and related reporting include Melissa Barthelemy, 24; Maureen Brainard‑Barnes, 25; Amber Lynn Costello, 27; Sandra Costilla, 28; Valerie Mack, 24; Jessica Taylor, 20; and Megan Waterman, 22. Four of those women - Barthelemy, Waterman, Costello and Brainard‑Barnes - have been identified in case files as the “Gilgo Four,” whose remains were found in 2010. Investigators say several victims were contacted from burner phones; the FBI helped link most of those calls to cell towers clustered in an area roughly a 20‑minute drive from Gilgo Beach. In the Amber Costello matter, a roommate described a client as an “ogre‑like” man who drove a first‑generation Chevrolet Avalanche and said Costello had been getting repeated calls from a client before she disappeared.

Pretrial fights are already shaping the calendar. The defense asked to split the case into separate trials and sought to block novel DNA technology from evidence; the judge denied both motions. With the DA’s written response deadline passed and a March 17 court appearance on the docket, Justice Mazzei has told the parties the trial will begin “right after” Labor Day, setting the stage for a months‑long battle over DNA evidence, the Word document, and the newly disclosed internet activity.