ABC News December 9, 2016

DA Urges NY State to Authorize Familial DNA Testing After NYC Jogger Murder Goes Unsolved

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The Queens District Attorney in New York City is urging the state to authorize familial searching of the state's DNA data banks in the wake of the unsolved murder of a young woman who was found strangled after she went for a jog.

Karina Vetrano, 30, was strangled to death on Aug. 2 on a path where she and her father often ran together in Howard Beach, New York. The case remains unsolved.

Queens District Attorney Richard Brown called "familial searching can be a powerful investigative tool" in Vetrano's case.

"All evidence recovered from [Vetrano's] body and the crime scene was submitted for DNA analysis. The tests found the same single male DNA profile under the victim’s fingernails, on her neck, and on her cell phone. The profile did not match any known offenders in the CODIS [Combined DNA Index System] data banks," Brown said in a letter to Michael Green, the executive deputy commissioner of the New York State Division of Criminal Justice and chairman of the New York State Commission on Forensic Science.

"This tragic murder has been exhaustively investigated using every tool currently available, but it remains unsolved," Brown said. "The killer remains at large, the public remains in danger, and the suffering of the victim’s family is amplified by law enforcement’s inability to yet solve this most awful crime. The victim, her family, and the public deserve justice and we have an obligation to use every means at our disposal to identify the murderer."

With familial searching, a crime scene DNA profile is run through a state data bank to see if links can be found to similar profiles belonging to a relative. The process uses special DNA testing on the Y chromosome, Brown said in his letter, referring to the chromosome found in males only.

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Nine states use familial DNA searching, Brown noted, including California.

In California, familial DNA led police in Los Angeles to find Lonnie David Franklin Jr., the infamous "Grim Sleeper," in 2010, after he eluded police for more than two decades. Franklin was arrested and charged with 10 counts of murder and one count of attempted murder, and this summer, he was sentenced to death.

But the New York Civil Liberties Union does not support the use of familial DNA searching.

"A policy that implicates New Yorkers in a criminal investigation solely because they are related to someone with DNA in the state's databank is a miscarriage of justice," a spokesperson for NYCLU said in a statement to ABC News. "The forensics commission cannot suspend a person’s constitutional rights against government invasion of their privacy simply because a relative had come under suspicion."

The NYPD is supporting Brown's plea and the request is being considered by the state.

The Vetrano family could not be immediately reached by ABC News for comment.

In August, Karina Vetrano's mother, Cathy Vetrano, told ABC News, "Right now, I am a broken, broken woman. ... But I want to say this: I am 100 percent confident that this person will be caught."

She pleaded with anyone who may be helping the killer evade police to come forward.

"That person, if you're harboring him -- if you're trying to protect him -- he could do it to you. He could do it to your loved one. Because he killed my daughter, not in self-defense, not because he had a fight with her, because he just killed an innocent, young, petite woman," she said.

"I beg of you to do what you know is right," she said. "Be courageous and make the phone call."

ABC News' Mark Crudele contributed to this report.