But California’s haste to expand its DNA database also shows the grave risks — to privacy and liberty — that unregulated familial searches can pose. If other states embrace this tool without adequate protections, they may put all of their DNA databases in legal and political jeopardy.
The biggest immediate concern is that familial searches are racially discriminatory. African-Americans represent about 13 percent of the United States population but 40 percent of the people convicted of felonies every year.
Hank Greely of Stanford Law School has estimated that 17 percent of African-American citizens could be identified through familial searches, compared with only 4 percent of the Caucasian population. Is it fair to subject African-American families to disproportionate genetic surveillance simply because one member of the family committed a crime in the past?
Some proponents of familial searches, like Dr. Frederick Bieber of Harvard Medical School, have insisted that "crime cluster[s] in families,” in language that echoes the discredited eugenic family studies of the early 20th century, with their discriminatory emphasis on “genetic criminality.” In a state with a history of tension between African-American citizens and the police, California’s familial searching policy may provoke a debate that makes the one over racial profiling look tame.
California’s familial searching policy may also jeopardize its attempts to store the DNA not only of convicted felons but of all people who are arrested, whether or not they are ultimately charged. The F.B.I. recently decided not to authorize familial searches, because Thomas Callaghan, the former head of the national DNA database, concluded that they could provoke a political and legal backlash that would threaten the federal government’s recent decision to begin storing DNA samples from arrestees.
Mr. Callaghan’s conclusion was well founded: in 2008, the European Court of Human Rights held that Britain’s decision to store the DNA samples of arrestees violated European privacy guarantees. The court was especially concerned that familial searches of arrestees could threaten the privacy of presumptively innocent people and they have proved less effective than searches of convicted felons' families.
California’s decision to include arrestees in its database is now being challenged in federal court. The possibility that the state might authorize familial searches of arrestees in the future may increase the likelihood that appellate judges will hold that including arrestees in the database is an unconstitutional search and seizure.
In addition to being limited, for the moment, to convicted felons, California’s familial searching policy includes another important privacy protection: it limits the use of the searches to cases with "critical public safety implications," in which no search of the offender's crime scene DNA has produced a direct hit or partial match. I can imagine a familial search program with additional limitations, codified in law, that might alleviate privacy concerns: it would be limited to the most serious violent crimes, would only search the familial DNA of convicted felons, not arrestees, and it would prohibit the government from sharing DNA samples with insurance companies, employers or schools, or testing them to predict antisocial behavior in the future rather than to solve violent crimes in the past.
Unfortunately, some proponents of familial searches have refused to endorse these moderate restrictions, which strike a sensible balance between privacy and security. As a result, familial searching of DNA databases may well increase without the “statutory guarantees of privacy” that the National Research Council of the National Academies demanded as early as 1992.
At some point in the not so distant future — if arrestees at a protest scene have their cheeks swabbed to see if their relatives committed minor crimes in the distant past -- we may wish that before rushing to expand the use of DNA databases, we had thought more carefully about the consequences.