DNA Databases and Familial Searching: Handle with Care

Posted by Pete Shanks March 24, 2011
Biopolitical Times

With great fanfare, California Attorney General Kamala Harris joined with Santa Cruz Police Chief Kevin Vogel and Santa Cruz District Attorney Bob Lee last week to announce the arrest of a suspect for sexual assault. To be precise, "suspicion of robbery, sodomy, sexual penetration by force and false imprisonment." Not only were there press releases, which led to widespread coverage, but video of Harris's statement is available from the State Department of Justice.

The crime, which took place in March 2008, was shocking news, locally. Police officers quickly chipped in $5000 to a reward fund, and community members more than doubled that. But the arrest, welcome as it may be, is not the kind of event that normally draws state-wide attention. In fact, this may be the first time that a California Attorney General has visited Santa Cruz on official business.

That's because of DNA. The suspect was identified because familial DNA searching turned up his father's identity as a probable close relative of the perpetrator. (No one gets the reward, because no one came forward with information.) That's what Harris was touting: "We're going to start solving a lot more crimes through the use of science and we're extremely excited about that."

Another way of putting that is to say that the success rate of California's familial DNA searching almost doubled last week. It rose from 8% to 15%! This is the technique's second success in 13 attempts since the procedure was authorized in 2008. To make the arrest, the cops not only had to use high-tech database analysis, they also had to root around in the suspect's trash, where they found a hairnet and a Gatorade bottle with traces of DNA that matched the original crime scene. That enabled them to get an arrest warrant, bust him on felony charges, take DNA with a cheek swab, and firmly establish the connection.

Rummaging through the garbage for discarded items that include DNA is presently legal in California. The State Supreme Court just declined to hear an appeal of an appellate decision [pdf] that upheld the stealthy acquisition of a discarded cigarette butt: the judges claimed there was no expectation of privacy for such trash, and therefore the Fourth Amendment does not apply. (That's also consistent with a different, controversial opinion the Supreme Court gave last May.) The ACLU and other legal experts disagree, but at least for now, that's the law in this state.

The first California use of familial DNA searching was last year's solving of the Grim Sleeper case in Los Angeles. That was about the most compelling scenario: a serial murderer who had baffled the police for years. The case provoked considerable comment about the appropriateness of California's guidelines, which were set out in some detail [pdf] by then–Attorney General Jerry Brown. Essentially, the technique is only to be used under strict supervision, for violent crimes where there is a usable DNA sample from the scene but no other leads.

The Santa Cruz crime does fall within the official guidelines but for all the publicity it's clearly a less dramatic case. And it's notable that the extensive media coverage did not include anywhere near as much discussion of the guidelines as last year. It would be strange if the process were routinized already, since only three cases in the country, including these two, have benefited from the technique. The other was a guy in Denver who broke into two cars, and eventually got probation. That case would not even have qualified for the process under California guidelines.

And yet, Virginia is boasting of adding this weapon to their forensic armory. New Mexico, Georgia, Idaho, Pennsylvania and Colorado, at least, are expanding their DNA databases—and the U.S. Senate is now considering a bill that would provide incentives to states to do so.

It's easy to understand the euphoria of a police department that cracked a three-year-old case, and indeed the public support for that success. However, the privacy issues are genuine and important; the huge disparity in racial inclusion in the databases is extremely disturbing; and there are questions as to whether reliance on DNA is the best use of scarce resources. The Council for Responsible Genetics has called on the President's Commission on Bioethics to consider the issue, while several states are considering more general DNA privacy rights. Moreover, faith in technology badly needs to be balanced with realism: just last week, another case was revealed where a forensics examiner "found DNA where it didn't exist, and failed to find it where it did."

Sharp tools are dangerous. They need to be handled with care and treated with respect. The photo op and cultivated press attention have much more to do with politics than with police work. A certain skepticism is in order.

Previously on Biopolitical Times: