Police Can Now Take Your DNA After Any Arrest

The Supreme Court has ruled that police can take DNA samples from anybody under arrest for any crimes, regardless of whether DNA is relevant to their arrest. The idea is to be able to connect people under arrest with other unsolved crimes using DNA, but the ruling has some worried about privacy and false accusations.

The 5-to-4 ruling saw a split in the usual conservative and liberal blocks, with conservative Antonin Scalia reading aloud his dissenting opinion—a measure taken only when the dissent is particularly intense (although it has become more common in the past few years).

The ruling looked at the case of Alonzo King, who was arrested in 2009 for menacing a crowd with a gun. A few days after the arrest, police took a swab from his cheek without a warrant and linked him to a rape that occurred six years earlier. King was convicted for that rape but appealed saying that the DNA swab amounted to unreasonable search, as there had been no warrant and no need based on the thing he had actually been arrested for. The Supreme Court’s ruling restored his conviction, saying that DNA swabs were more like fingerprinting and photographing, than like searching—saying that a “gentle” swab of the cheek wasn’t invasive enough to be considered a search.

Marcus L. Brown, superintendent of the Maryland State Police, told NPR he was quite pleased with the result. “We view as sort of the modern fingerprint,” he said. As DNA tools have become cheaper and more reliable, many say that collecting this information could help solve cold cases sitting on shelves.

But not everyone is happy with the ruling. Scalia said in his dissent, “Because of today’s decision, your DNA can be taken and entered into a national database if you are ever arrested, rightly or wrongly, and for whatever reason.” And the ACLU agreed with him, saying:

“Today’s decision creates a gaping new exception to the Fourth Amendment. As Justice Scalia’s dissent convincingly demonstrates, DNA testing of arrestees has little to do with identification and everything to do with solving unresolved crimes. While no one disputes the importance of that interest, the Fourth Amendment has long been understood to mean that the police cannot search for evidence of a crime – and all nine justices agreed that DNA testing is a search – without individualized suspicion. Today’s decision eliminates that crucial safeguard. At the same time, it’s important to recognize that other state laws on DNA testing are even broader than Maryland’s and may present issues that were not resolved by today’s ruling.”

Boston University law professor Tracey Maclin told NPR that a DNA swab certainly felt different than fingerprinting. “This is not just searching somebody’s purse or knapsack who’s been placed under arrest — or even searching their car,” Maclin said. “We’re searching their person in a situation where we don’t have any basis for the search other than the fact that the guy’s been arrested.”

Of course, many people who are arrested have done nothing wrong at all. That doesn’t keep them from being swabbed. Here’s Popular Science:

A racist cop who pulls over a guy driving a car in Arizona because he looks Latino? That guy can now have his DNA taken and booked on file, even when he’s released in an hour with no charges filed.

And some argue that DNA evidence isn’t as important or useful as you might see on television. The Innocence Project—an organization that represents people that have been wrongfully convicted—has some statistics:

While DNA exonerations are a window into the effect of unvalidated or improper forensic science contributing to wrongful convictions, DNA does not solve the problem. In fact, experts estimate that only 5-10% of all criminal cases involve biological evidence that could be subjected to DNA testing. In the other 90-95% of crimes, DNA testing is not an option – so the criminal justice system relies on other kinds of evidence, including forensic disciplines that may not be scientifically sound or properly conducted.

There are some safeguards in place in the law in Maryland, where King was convicted. There, the samples can’t be processed without a suspect’s consent until they’re arraigned. The samples must be destroyed if the charges are dropped or the person is acquitted. And they can only be taken from those suspected of violent crimes or burglary. But not all states have these safeguards. And Justice Kennedy, who wrote the court opinion, admits that without them this could be a very different case. Here’s the Wall Street Journal:

Justice Kennedy stressed those protections in upholding the Maryland statute. But “if in the future police analyze samples to determine, for instance, an arrestee’s predisposition for a particular disease,” additional court review could be necessary, he wrote.

Right now, 28 states have practices that allow law enforcement agents to swab on arrest, so this certainly won’t be the last time the court hears cases on DNA, and perhaps not even the last time it thinks about these sorts of searches.

More from Smithsonian.com:

This Gun Shoots Criminals With DNA
Books of the Future May Be Written in DNA

Rose Eveleth | | READ MORE

Rose Eveleth was a writer for Smart News and a producer/designer/ science writer/ animator based in Brooklyn. Her work has appeared in the New York Times, Scientific American, Story Collider, TED-Ed and OnEarth.