DNA evidence

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Defense lawyers for a man identified as a double-murder suspect through family tree DNA focused on a different forensic issue—a palm print—during his trial on Tuesday.

The defendant, 56-year-old William Talbott II, is accused of the November 1987 murders of a young Canadian couple killed during a trip to Seattle. He was charged after genetic genealogist CeCe Moore of the TV series Finding Your Roots built a family tree by uploading the DNA profile from semen found on the victim’s clothing to GEDmatch, the Associated Press reports.

After the DNA sleuthing identified Talbott, police collected DNA from a cup he used. The DNA matched the semen.

Talbott’s case is the first murder case using family tree forensics to go to a jury trial, according to Wired. The family tree technique has helped identify suspects in at least 50 cases.

In Talbott’s trial this week, the defense grilled a state crime lab analyst who initially concluded that a palm print in the van used by the victims did not belong to Talbott, according to coverage by HeraldNet. The analyst, Angela Hilliard, said she changed her opinion after realizing she was looking at the palm print upside down.

“Unfortunately, it’s because I’m human,” Hilliard said in explaining her error.

The woman who was killed, Tanya Van Cuylenborg, had died from a gunshot wound to her head. The other victim, Jay Cook, had been beaten with rocks and strangled with twine.

In opening statements in the case, defense lawyer Jon Scott argued that genetic genealogy can give prosecutors insight into who left biological evidence, but it doesn’t establish whether the individual was the perpetrator of a crime. Wired had coverage.

No matter what the result in Talbott’s case, legal challenges to the technique could unfold for years, according to Wired.

Writing for the New York Times, University of California at Davis law professor Elizabeth Joh says police use of genetic genealogy is virtually unregulated. “There are not only few rules about which crimes to investigate,” Joh says, “but also unclear remedies in the case of mistakes, the discovery of embarrassing or intrusive information or misuse of the information.”

Though you may consent to police using your DNA profile when you post it online, it is also exposing your relatives and future generations without giving them a chance to opt out, Joh says. She suggests legislators and the Federal Trade Commission should create guidelines for law enforcement’s use of the technology.