Two new laws restrict police use of DNA search method

In other cases, detectives may surreptitiously collect DNA from a relative of a suspect by testing an item the relative has thrown in the trash.

Maryland’s new law says that when police test the DNA of “third parties” – people other than the suspect – they must first get their consent in writing, unless a judge approves the deceptive collection.

Investigators cannot use any of the genetic information collected, whether from the suspect or from third parties, to learn more about a person’s psychological traits or predispositions to disease. At the end of the investigation, all genetic and genealogical records that have been created for her must be deleted from the databases.

And perhaps most importantly, Maryland investigators interested in genetic genealogy must first try their luck with a government-run DNA database called Codis, whose profiles use far fewer genetic markers.

Mr. Holes said that this part of the law could have tragic consequences. For old cases, he pointed out, DNA evidence is often very degraded and fragile, and each DNA test consumes some of that precious sample. “Essentially, the law could potentially have me kill my case,” he said. And given the speed at which DNA technology is changing, he added, it is not wise for a law to mandate the use of any particular type of test.

But other experts have called this provision crucial, because the potential breach of privacy is much more serious for genetic genealogy, which gives law enforcement access to hundreds of thousands of genetic markers, than for Codis, which only uses about twenty markers.

These searches are “the equivalent of the government going through all of your medical records and all of your family records just to identify you,” said Leah Larkin, a genetic genealogist who runs a consulting business in the San Francisco Bay Area who is largely concentrated. to help adoptees and others find their birth parents. “I don’t think people fully appreciate the amount of your genetic data.”

Brandon D. James