California will adopt the most aggressive approach in the nation to a controversial crime-fighting technique that uses DNA to try to identify elusive criminals through their relatives, state Atty. Gen. Jerry Brown announced Friday.

Employing what is known as familial or “partial match” searching, the policy is aimed at identifying a suspect through DNA collected at a crime scene by looking for potential relatives in the state’s genetic database of about a million felons. Once a relative is identified, police can use that person as a lead to trace the suspect.

The new plan makes California a leader in such searches, which several states permit but do not vigorously pursue. Colorado has recently begun to examine its database for relatives of unknown criminals as part of a research project.

Brown said the new approach was justified by violent crime plaguing the state. He emphasized that it would be used only when all other leads had been exhausted.


“We have 2,000 murders a year in California -- that is 10,000 since the Iraq war started -- and that is a lot of killing,” Brown said. “When you see it and see the victims and have to go to funerals, it is pretty serious stuff.”

But Tania Simoncelli, science advisor to the American Civil Liberties Union, called Brown’s decision a disappointment and said the organization is exploring its legality. The group has not decided whether to challenge the policy in court.

“The fact that my brother committed a crime doesn’t mean I should have to give up my privacy,” she said.

At a recent FBI conference on familial searching, Jeffrey Rosen, a constitutional law professor at George Washington University, warned: “I can guarantee if familial searching proceeds, it will create a political firestorm.”


The policy, which takes effect immediately, is designed to work like this: The state’s crime lab will tell police about DNA profiles that come up during routine searches of California’s offender database and closely resemble, but do not match, the DNA left at a crime scene. (Previously, the state refused to tell police about these partial matches.)

The lab will then perform calculations and tests to determine the likelihood of a biological relationship between the person found in the database and the unknown offender believed to have left DNA at the crime scene.

When such partial matches do not surface or fail to produce a lead, a more customized familial search can be done in which computer software scans the database proactively for possible relatives. The software measures the chance of two people being related based on the rarity of the markers they share.

California appears to be the first state in the nation to use this second technique as a matter of policy. Drafted with the heavy involvement of lawyers, the new policy requires a series of meetings with police and prosecutors to ensure that the relative’s name is vital to the investigation and that all other leads have been exhausted.


Once a relative has been identified, police can interview him or construct a family tree based on existing records. If a suspect is identified, police can obtain a warrant for his DNA, or even gather it surreptiously from an abandoned drink or cigarette butt. The suspect’s DNA sample would then be compared to the crime scene sample and possibly used as evidence.

“The people of California will know that we are using the database to try to solve as many crimes as we can, unlike virtually every other state in the country,” said retired Alameda County Dist. Atty. Rockne P. Harmon, who consulted with the state on the policy.

Civil libertarians oppose using DNA databases to search for relatives of unknown offenders, saying it puts family members under “genetic surveillance” for crimes they did not commit. For now, all the people in the state’s database are convicted offenders, but the state plans to expand the database next year to include arrestees, heightening concerns over privacy.

Critics say familial searching could expose sensitive and secret genetic relationships. A son, for example, could learn that his father was not his biological parent. DNA databases also reflect the racial and ethnic biases of the justice system, exposing minority communities to more surveillance than others, critics maintain.


FBI officials in charge of the national database network have also expressed concerns, making them unlikely allies of civil libertarians on familial searching. They urge a cautious approach, worrying that the courts will balk at this type of sleuthing. No law specifically authorizes it, and some legal scholars consider it unconstitutional because they say it amounts to an unreasonable search.

Brown called such objections hypothetical. The policy forbids the release of the names of relatives until genetic tests and analysis convince the state that the person is indeed a relative.

“It is still not going to be a fail-safe system, and we are going to make mistakes,” said Simoncelli, the ACLU science advisor. “We are opening the door to using the database in such a fundamentally different way than the purpose for which it was established.”

No one knows how well the state’s plan will work. Harmon said he was absolutely convinced that it would provide at least some new leads for police.


Lance Gima, the state’s top forensic scientist, agreed. But he conceded that the search for relatives would be a longshot because many unrelated people share genetic markers. He said he hoped the state’s decision would spur technology to improve the accuracy of such searches.

Britain has done familial searching for years, using more sophisticated software. With a 10% to 14% rate of identifying perpetrators, Britain’s searches have had limited but dramatic results, cracking some sensational crimes.

A serial rapist whose DNA was not in Britain’s national database was caught because he was genetically similar to his sister, whose DNA was taken after a drunk-driving arrest. The so-called shoe rapist had a fetish for stiletto heels. When police captured him, they discovered scores of high heels he had stolen from his victims.

Police in the U.S. have used genetic relationships to help catch criminals in a different way, and on a much smaller scale.


After Kansas police zeroed in on the serial killer who dubbed himself BTK -- initials for bind, torture, kill -- they obtained a court order for the pap smear of his daughter. Without her knowledge, police performed a DNA analysis of the specimen, obtained from a medical laboratory.

The genetic similarities indicated they had the right man, Dennis Radar.

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maura.dolan@latimes.com


jason.felch@latimes.com