Swabbing suspects

U.S. Supreme Court justices today heard arguments in a case that tests the boundary between genetic privacy and the ability of law enforcement agencies to solve crimes. At issue is whether police can collect DNA samples from suspects who have been arrested but not convicted of a crime, for the purpose of linking them to past, unsolved cases.

Today’s case, Maryland v. King, draws attention to the growing national database of DNA samples that state and federal officials have collected from suspects and convicted criminals. Police and victims’ advocacy groups say the database serves justice by matching DNA from unsolved murder and sexual assault cases with samples taken from suspects arrested for new crimes. But privacy groups say the database allows the government to store too much information about potentially innocent citizens.

If the high court rules against the DNA database, states might have to throw out thousands of cheek swabs collected from suspects over the years.

The central figure in the case is Alonzo Jay King Jr., who was arrested in 2009 on two charges of assault for aiming a shotgun at several people. After the arrest, Maryland police swabbed King’s cheek, which they were allowed to do since one of the crimes he was accused of was a felony.

Comparing King’s DNA sample with a national database, investigators found it matched an unsolved rape case from 2003. In Wicomico County, Md., a 53-year-old woman had been assaulted after a masked man brandishing a gun broke into her home. King was convicted of the crime and sentenced to life in prison.

But King’s lawyers protested that the DNA sample shouldn’t have been admitted as evidence in the rape trial, because he was never convicted of the 2009 felony assault (instead, he had pleaded guilty to a lesser misdemeanor charge). A Maryland court ruled in favor of King last year and threw out his rape conviction, to the chagrin of state police. The Maryland court’s decision stands in conflict with federal courts and the Virginia Supreme Court, which have upheld DNA collection laws similar to the one in Maryland.

At Tuesday’s hearing, Kannon Shanmugam, King’s attorney, told the justices, “Maryland searched my client without a warrant in order to investigate crimes for which there was no suspicion.” Since the DNA sample was being catalogued to connect King to crimes unrelated to his arrest, Shanmugam argued the state didn’t have a right to collect his DNA without a warrant. He should have been treated as a normal citizen in that respect.

Justice Elena Kagan seemed to follow that line of thinking: “Assume you’ve been arrested for something. The state doesn’t have the right to go search your house for evidence of unrelated crimes, isn’t that correct?”

Katherine Winfree and Michael Dreeben, attorneys for Maryland and the Obama administration, countered that once a person is arrested, he enters a separate category from other citizens and has a “reduced expectation of privacy.”

Chief Justice John Roberts asked whether law enforcement could extract other information from collected DNA samples beyond a predetermined set of data points used to find matches with other crimes. Dreeben said they legally could not, making the expectation of privacy less significant: The DNA sample is only used to identify the person, such as a fingerprint would.

At the heart of the case is whether collecting DNA from people not yet convicted of crimes violates the Fourth Amendment. It reads in part, “The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause. …”

Police and investigators argue collecting DNA samples is similar to the routine practice of collecting fingerprints and wallets from suspects. Maryland State Police Superintendent Col. Marcus L. Brown told me in a statement he supported collecting DNA from people charged with violent crimes because it gives police “the ability to identify persons responsible for crime sooner” and reduces their chance of committing additional crimes.

Justice Samuel Alito Jr. said he thought the case was “perhaps the most important criminal procedure case that this court has heard in decades.”

All 50 states have expressed support for Maryland in the case. Each state in the union already collects genetic samples from convicted criminals, and the federal government and over half the states collect DNA from people suspected of certain crimes. The states and federal officials combine their databases to form the FBI’s Combined DNA Index System (CODIS), which currently contains more than 10 million profiles of convicted criminals and nearly 1.4 million more from people arrested on suspicion of an offense. According to the FBI’s website, DNA matches discovered through CODIS had assisted in 192,400 investigations as of January.

In 2011, out of 10,666 DNA samples taken in Maryland, 19 led to arrests after being matched to other cases. Advocacy groups for victims of crimes support DNA collection as a cutting-edge way of apprehending criminals and exonerating innocent people accused of crimes—a tool for serving justice to victims’ families, who often wait years to bring closure to cold cases.

The state and federal databases find matches using a limited set of DNA data points, and don’t store personal information like names. But some privacy rights groups, including the American Civil Liberties Union and the Electronic Frontier Foundation, worry the government’s growing collection of DNA could lead to misuse. Not all states expunge arrestee DNA samples from their databases when the person is later acquitted of charges.