by Jen Acker
When DNA is left behind at a crime scene, investigators usually run the sample through a DNA database. All states collect DNA samples from convicted felons, and some even collect DNA from suspects brought into custody. If the DNA found at the crime scene matches a sample in the database, a suspect has likely been identified. Sometimes, an exact match may not be found, but a very close match may exist: this is the essence of familial DNA searching. These near-matches may spell trouble for the innocent relatives of people with criminal histories.
Individuals related by blood have similarities in genetic material. Therefore, the stored DNA of a man who has a criminal record could be used to identify his brother who does not have a criminal record. Similarly, DNA taken from children born out of a rape has been used to identify their father, the rapist. In at least one high profile case, familial DNA searching was used to free an innocent man who spent 19 years behind bars.
Despite the potential for identifying suspects, familial searching is not without debate, and its legality has not been vetted in the courts. Critics contend that familial DNA searching raises concerns regarding privacy and illegal search and seizure. While DNA near-matches indicate that a relative of a convicted criminal is likely implicated, near-matches do not indicate precisely which relative. The fear is that family members become guilty by DNA association even when law enforcement has no other evidence to support the connection.
The Science Progress blog surveyed all 50 states; 32 of the 39 states that responded have policies or laws regarding familial searching. Policies differ by state regarding variations on how the near-match was identified: partial match reporting is different from familial searching. Partial match reporting occurs where DNA testing labs inform law enforcement agencies of near-matches discovered during testing. Familial searching, on the other hand, occurs at the request of law enforcement officials, who actively initiate searches for near-matches. On the whole, states are less willing to permit or approve requests for familial searches. Meanwhile, states with no policies often have no articulated restrictions on how labs should report partial matches, if at all.
Among the states that have articulated policies, Maryland expressly forbids familial searching. California arguably has the best-implemented policy; it is one of a handful of states to make its policy easily accessible to lab technicians and law enforcement alike. Often, these policies are made available only to lab technicians. Currently, California does not permit familial searches of its arrest databases, which protects the DNA privacy of individuals who are arrested, but not convicted of crimes. Furthermore, labs that discover partial matches must perform an additional level of testing, YSTR analysis, before reporting the identities of potential suspects to law enforcement officials. By comparing Y chromosomes, YSTR testing can determine whether the DNA samples in question are from related males.
Usually, judges decide whether to permit familial DNA searching on a case-by-case basis. And, fortunately, once a DNA near-match has been discovered, its existence is typically not enough evidence to compel an innocent person to provide law enforcement agents with a DNA sample. There must be other physical evidence that links the near-match suspect to the crime scene to find the sample request constitutional.
Other critics contend that familial searching runs counter to Congressional intent behind establishing DNA databases in the first place.
In the leading case upholding the collection of DNA samples, U.S. v. Kincade, the U.S. Court of Appeals for the 9th Circuit stressed in 2004 that the government had two good reasons for requiring people on probation to provide a DNA sample: the diminished expectation of privacy that people have once they’re on probation, and the state’s strong interest in ensuring that they reform rather than becoming recidivists and commit new crimes in the future.
Where the creation of DNA databases was justified on the basis that convicted criminals had lost the right to the privacy of their DNA, familial DNA searching suggests that their family members have lost their DNA privacy by association. Additionally, familial searching has no role in deterring previously-convicted criminals from committing future crimes. In some instances, familial searching also challenges federal laws that forbid sharing information across state lines about people who are not suspects.
Finally, general racial disparity in convictions also concerns critics of DNA familial searching. One researcher estimates that based on the racial makeup of the prison population, 17 percent of African-Americans in the general population could be identified through familial searching, while only 4 percent of Caucasians could be identified this way.
Given the increase in DNA cataloguing, including among arrestees and even for health-related purposes, states would be wise to prohibit familial searching and partial match reporting in favor of safeguarding our privacy and Fourth Amendment due process rights. Justice is not served by requiring innocent people to turn over their DNA.