We wrote earlier this year on the Fourth Amendment issue presented in Maryland v. King: whether a Maryland statute that allows the state to obtain DNA samples via “cheek swabs” from arrested individuals, as one step in the state’s routine booking and processing procedure, is an invalid warrantless search.

Maryland takes its samples before any finding of guilt has been secured. To go one step further, these samples are, in most instances, factually unrelated to any aspect of the offense being investigated or charged. Instead, Maryland uses the DNA samples as a comparative tool: it tries to match the samples with DNA evidence from other “cold” unsolved crimes. The swabs are taken even though there may be no articulable “individualized suspicion” that a particular arrestee may have had anything to with any prior offense.

The dispute started with Mr. King, who was arrested for menacing a group of people with a shotgun and, accordingly, charged with assault. Under Maryland’s “DNA Collection Act”, a police employee rubbed the inside of Mr. King’s cheek with a cotton swab during the arrest booking procedure. This yielded a DNA sample, which was then uploaded onto a computerized database. Mr. King’s DNA was found to match a DNA sample from an unsolved rape in 2003.

Mr. King was indicted for that rape and a second DNA sample, obtained via a search warrant this time, confirmed the match. His motion to suppress the DNA evidence was denied by the trial court and Mr. King was duly tried, convicted and sentenced to life in prison without parole.

The Maryland Court of Appeals reversed, finding that the taking of DNA evidence from suspects, arrested but not yet convicted, violated the Fourth Amendment, as the individual’s expectation of privacy outweighed the State’s interest in using Mr. King’s DNA.

The Supreme Court’s decision came on June 3rd, a 5-4 opinion authored by Justice Kennedy, joined by Chief Justice Roberts, and Justices Alito, Thomas and Breyer.

The majority upheld the swab procedure; while finding it to be a search, the Court nevertheless classified it as a minimal warrantless intrusion and a reasonable exercise of state power.

The Court spoke at length about the prevalence of DNA testing and analysis in society and its proven reliability, citing District of Attorney’s Office v. Osborne for its discussion of the technology’s power to both identify the guilty and exonerate the innocent.

The Court placed reliance on some protective aspects of the Maryland statute: that samples are only taken from people arrested for “serious” offenses, that the sampling process is delayed until after arraignment (thus presumably exempting cases dismissed early or charged mistakenly) and that the samples are destroyed if the suspect is acquitted or the charges dismissed.

The gist of the Court’s opinion is really that DNA sampling is now a routine part of law enforcement practice—on par with fingerprinting and photography in the routine identification and processing of suspects, that Mr. King’s privacy was not intruded upon by the swab and that Maryland’s statute was reasonable.

Justice Scalia dissented, joined by Justices, Ginsburg, Sotomayor and Kagan. (This interesting breakdown of justices, both in the majority and dissent, has been heavily commented on).

The Scalia dissent is wonderfully written and worth reading for its literary merit alone. The dissent argued, among other points, that in order to be constitutionally permissible, warrantless searches have traditionally had to present a justifying motive above and beyond the mere investigation of crime.

As Justice Scalia stated “… suspicion less searches are never allowed if their principal end is ordinary crime solving.” This, to the dissent, seems to have been the critical limitation—the complete disconnect between the Maryland testing and the crime Mr. King was charged with. Searching every car on the road or doing DNA testing on every airplane passenger might also prove a boon to crime prevention, Scalia argued, but the system is just not built that way.

King is a major Fourth Amendment decision and a must read. Justice Scalia’s views on the Fourth Amendment are just consistently fascinating and well worth following.