The Supreme Court's decision today to uphold Maryland's law allowing the collection of DNA samples from people arrested for serious crimes upholds the interests of justice, the Constitution and common sense. Concerns that the DNA samples could violate suspects' privacy were unfounded, the practice of taking the samples is less intrusive than other searches authorized under the Fourth Amendment, and the direct result of a ruling against the law would have been the possibility that a known rapist would be released onto the street.
The case in question, Maryland v. King, centers on an Eastern Shore man, Alonzo Jay King Jr., who was arrested in 2009 on assault charges. Before he was convicted of that crime, police took a DNA sample pursuant to Maryland's new law allowing for such collections at the time of arrest in certain offenses, a key public safety initiative of Gov. Martin O'Malley. The DNA matched a sample from an unsolved 2003 rape case, and Mr. King was convicted of that crime. He appealed, claiming that the DNA sample violated his Fourth Amendment protections against unlawful searches and seizures. Maryland's Court of Appeals agreed with him and overturned his rape conviction, making a number of errors along the way.
The case was an important one for the court to decide, as several lower court decisions had come to varying conclusions on the constitutionality of taking DNA samples before conviction. The case scrambled the traditional liberal-conservative lines on the Supreme Court. The majority decision was written by Justice Anthony Kennedy (often a swing vote) and joined by conservative justices John Roberts, Clarence Thomas and Samuel Alito and liberal Justice Stephen Breyer. Justice Antonin Scalia, a conservative, wrote the dissent, which was joined by justices Ruth Bader Ginsberg, Sonia Sotomayor and Elena Kagan, all liberals. It also overrode the traditional political differences between the states, as 49 of them, plus Puerto Rico and Washington, D.C., joined Maryland with amicus briefs.
The Supreme Court's majority ruled that Maryland's DNA statute serves a legitimate government interest in verifying the identity of those it has probable cause to take into custody on suspicion of certain crimes — the state law limits pre-conviction DNA collection to those charged with crimes of violence or burglary, or the attempt of those crimes. Crucially, the court notes that a person's "identity" constitutes far more than his name but also includes past conduct or criminal history. Indeed, the majority opinion notes, police already routinely seek to connect arrestees to other offenses through comparisons of mug shots and fingerprints. "The only difference between DNA analysis and fingerprint databases is the unparalleled accuracy DNA provides," Justice Kennedy wrote. That's important not only in that it can connect an arrestee to a previous, unsolved crime, as in the case of Mr. King, but because it can help exonerate the innocent and free the falsely convicted. It can also help the state make appropriate decisions about bail because it will provide a better sense of a suspect's flight risk or potential danger to the public.
From a physical standpoint, it is clear that collecting a DNA sample is not intrusive. The procedure in Maryland and most other places with similar laws is to collect a sample of cells by rubbing something like a cotton swab on the inside of a suspect's cheek. The procedure is essentially painless and risk-free. The more pertinent question is whether the collection of DNA presents a greater risk to a suspect's privacy than do already existing methods of identification. Maryland's Court of Appeals, and some civil liberties advocates, have expressed concern that a database of individuals' DNA could provide the state with information about their propensity for disease or other characteristics. That concern is unfounded. Maryland law specifies that only what is known as "non-coding" sections of DNA — that is, parts of the genetic code that serve no known function but which are nonetheless unique to each individual — are uploaded into the database. Moreover, the law sets strict limits on how the information can be used and under what circumstances it may be kept.
Justice Scalia's lively dissent rejects the idea that "identity" amounts to anything more than connecting a name to a person and argues that DNA collection from arrestees serves only as a means to seek evidence to solve unrelated crimes. His objections miss the mark. DNA itself is not evidence of a crime any more than fingerprints or mug shots. And if the use of DNA in this regard is unconstitutional, so, too, is the collection and analysis of fingerprints that has been standard practice for decades. His argument that the speedier processing of fingerprints than DNA makes them different is unconvincing, given that the technology that makes instant fingerprint matching possible has only been around since 1999.
It is important not to lose sight of what is at stake here. The result of the court's decision is that Mr. King will not go free. Nor will at least 50 other criminals who were convicted in Maryland based on DNA evidence collected from arrestees. Maryland's law strikes a careful balance between our rights to privacy and our interest in determining whether arrestees have committed prior crimes. The court's decision serves the interests of both public safety and justice.