A divided three-judge panel of the 9th U.S. Circuit Court of Appeals ruled that a 2004 California law requiring officials to collect the DNA samples does not violate the U.S. Constitution's ban on unreasonable searches.

"DNA analysis is an extraordinarily effective tool for law enforcement to identify arrestees, solve past crimes, and exonerate innocent suspects," Judge Milan Smith wrote for the 2-1 majority. The government's interests in the genetic information outweigh any privacy concerns, the majority concluded.

The DNA samples, from a swab of an inmate's cheek, are analyzed for certain identifying markers and the information is then stored in a nationwide database. Someone who is tested and not convicted can ask to have the sample destroyed and their DNA profile removed from the database.

Four California residents, who had been arrested for felonies but who were not convicted, filed a class action in 2009 against officials who run the state's DNA collection system. They asked the court to issue an order barring California from collecting DNA samples from people who were arrested but not convicted. The district court rejected that request, and the 9th Circuit upheld that decision.

The appeals court found that the arrestees' DNA profiles contained such minimal information that they were comparable to traditional fingerprints.

But Judge William Fletcher dissented. Fingerprints are taken to identify a person upon arrest, whereas DNA samples "are taken solely for an investigative purpose, without a warrant or reasonable suspicion," he wrote.

"The majority allows the government to treat arrestees, who are presumed innocent, as if they've been convicted of some sort of crime," said Michael Risher, an attorney with the American Civil Liberties Union who represented the plaintiffs. He said his clients would seek review by the full 9th Circuit.

California Attorney General Kamala Harris praised the ruling as "a victory for public safety in California." She said in a statement that the collection of DNA from adult felony arrestees had helped solve thousands of crimes.

Many states, as well as the federal government, have passed laws requiring people who are arrested to provide their DNA. Last year, in United States v. Mitchell, the 3rd Circuit upheld DNA testing as "an accurate, unique, identifying marker - in other words, as fingerprints for the twenty-first century." Ruben Mitchell, who was charged with intent to distribute cocaine, has appealed that case to the Supreme Court.

(Reporting by Terry Baynes; editing by Eddie Evans and Eric Beech)

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