Gilgo Beach killings: Suspected serial killer Rex Heuermann's DNA not a match to 1994 murder scene, ME rules

DNA found at the scene of the 1994 killing of Colleen McNamee does not match that of accused Gilgo Beach killer Rex A. Heuermann, the Suffolk County Medical Examiner’s Office announced in response to a judge’s order to compare the two profiles.

"Rex Heuermann is excluded as ‘unknown male A,’ " a forensic scientist with the office of the medical examiner determined in an Oct. 21 lab report.

The analysis was done following Suffolk Supreme Court Justice Richard Ambro’s Oct. 10 ruling on requests by twice-convicted killer John Bittrolff, who had sought to have his murder convictions overturned.

Ambro declined to vacate the convictions but ordered the analysis, saying the presence of the unknown DNA had the "potential to create a reasonable probability" the verdict could have been different if the evidence was presented to the jury and proved to have originated from Heuermann.

Ambro had stayed his order until Oct. 7 to give the Suffolk County District Attorney’s Office an opportunity to "consider any further action." Prosecutors responded Wednesday by filing the lab report that shows the unknown profile was compared with a Suffolk crime lab sample of Heuermann’s DNA obtained through a buccal swab on Oct. 10, 2023, and proved to not be a match.

The order did not require the prosecution to compare the DNA with any other profiles and the analysis makes no determination as to who the contributor was. Ambro denied the defense's other requests to conduct mitochondrial DNA testing and compare the sample with the FBI's CODIS database.

Bittrolff's attorneys from the Legal Aid Society of Suffolk County Appeals Bureau said in an Oct. 14 statement to Newsday they were grateful the DNA analysis would be conducted but were also "greatly disappointed" Ambro had not vacated their client’s conviction.

"Grave injustice occurred throughout the prosecution of Mr. Bittrolff," the attorneys said, pointing to the reliance on sperm density evidence for a conviction and the existence of another man’s DNA at the scene. "Mr. Bittrolff did not receive a fair trial," the defense wrote.

Bittrolff, a Manorville carpenter, was found guilty in 2017 in the cold case killings of McNamee and Rita Tangredi, whose remains were found months earlier in East Patchogue. The other man's genetic material was found on a pair of "men’s jeans" discovered at the McNamee crime scene in Shirley, a pair of black stretch pants and on the victim.

Suffolk prosecutors had urged the judge to deny the motion to vacate the conviction, arguing it was a misguided attempt to connect Heuermann to the killings.

Prosecutors also argued that both sets of pants belonged to McNamee and the DNA profile is likely of a man who had sex with her before Bittrolff.

Bittrolff's attorneys filed the motion in January after they said reanalyzed DNA evidence in McNamee's killing showed the new unknown profile.

"Defendant has neither demonstrated a nexus between Rex Heuermann and Ms. McNamee, nor provided an adequate legal basis to perform a comparison of Heuermann’s DNA — which is not evidence in this case," Assistant District Attorney Rosalind Gray wrote in May.

Heuermann has pleaded not guilty in the killings of seven women, including the 1993 death of Sandra Costilla, who were all said to have engaged in sex work. Both McNamee and Tangredi were known sex workers and Suffolk investigators previously said the killer of the two women might also be responsible for Costilla’s death.

Following Bittrolff's sentencing, the lead prosecutor, former Assistant District Attorney Robert Biancavilla said he believed Bittrolff was responsible for Costilla and possibly other Gilgo Beach killings.

 Heuermann's attorney, Michael J. Brown, of Central Islip, said he agrees with "both Bittrolff's appellate attorneys and the district attorney's office." 

"Biancavilla indicated that Bittrolff was not only responsible for his two murders but also the Costilla murder and other Gilgo Beach victims," Brown said. "The Legal Aid Society vehemently argued that the responsible party for the victims was the same suspect as the Costilla murder. Thankfully, the Suffolk County crime lab has now excluded Heuermann as a suspect in the Bittrolff murders."  

Ambro earlier signed a subpoena in 2024 directing the Suffolk County District Attorney’s Office to provide Bittrolff’s appellate attorneys with the raw DNA data in the McNamee and Tangredi cases, court records show.

 Cybergenetics, a DNA company with proprietary software using computer "probabilistic genotyping" determined Bittrolff was not a contributor to the male DNA found on the jeans, stretch pants and a separate swab of McNamee’s body.

Bittrolff was arrested in July 2014 after investigators learned DNA found at both crime scenes partially matched the DNA of one of his brothers.

Bittrolff was later identified as a match for the DNA found on two swabs of Tangredi, a swab of McNamee and fingernail scrapings of Tangredi’s left hand. 

Newsday's Nicole Fuller contributed to this story.