LOS ANGELES - Dozens of police departments around the U.S. are amassing their own DNA databases to track criminals, a move critics say is a way around regulations governing state and national databases that restrict who can provide genetic samples and how long that information is held.
The local agencies create the rules for their databases, in some cases allowing samples to be taken from children or from people never arrested for a crime. Police chiefs say having their own collections helps them solve cases faster because they can avoid the backlogs that plague state and federal repositories.
DNA is found in cells and provides a genetic blueprint unique to each person. Blood, saliva, semen, hair, and skin are among the biological clues a criminal might leave at a crime scene and investigators need only a few cells to create a profile.
Police typically get a DNA sample by swabbing the inside of a person's mouth. That sample can then be compared against others in a database to see if a match occurs.
Some police departments collect samples from people who are never arrested or convicted of crimes, though in all such cases the person is supposed to voluntarily comply and not be coerced or threatened.
State and federal authorities typically require a conviction, arrest or warrant before a sample is entered into their collections.
"The local databases have very, very little regulations and very few limits, and the law just hasn't caught up to them," said Jason Kreig, a law professor at the University of Arizona who has studied the issue. "Everything with the local DNA databases is skirting the spirit of the regulations."
It's unclear how many police departments maintain their own DNA databanks because they are subject to no state or federal oversight, but police in California, Florida, Connecticut and Pennsylvania have spoken publicly about their local databases.
In San Diego, in addition to voluntary samples taken from adults, police officers are allowed to take samples from juveniles who aren't arrested or convicted as long as they are for investigative purposes and the children sign a consent form. After the sample is taken, a police officer is required to contact the child's parent or legal guardian to tell them a DNA swab was collected.
The American Civil Liberties Union filed a lawsuit against San Diego last month alleging the policy "purports to sideswipe" restrictions implemented by a California state law that bars those samples from being entered into the state's DNA database.
When police officers take DNA samples from children without a court order, "it's hard to imagine it's anything other than coerced or involuntary," said Bardis Vakili, an ACLU attorney who is spearheading the lawsuit.
"I think they are trying to avoid transparency and engage in forms of surveillance," he said. "We don't know what's done other than it goes into their lab and is kept in a database."
Watch the ACLU's news conference on the lawsuit here:
A San Diego police spokesman declined to comment on the lawsuit and wouldn't provide additional information about the department's policy.
San Diego, the nation's eighth-largest city, has about 1.4 million people and a very large database, while Branford, Connecticut, population 28,000, has just 500 samples in its collection.
Still, Chief Daniel Halloran said the database has helped solve crimes and eliminate other people as suspects. The department has implemented strict guidelines to ensure samples are voluntary and they do not take samples from juveniles, he said.
"It's not like we're pulling over motorists and asking them for DNA," Halloran said. "There has to be some sort of correlation to a crime."