Supreme Court Justice Samuel Alito called it "the most important criminal procedure case that this court has heard in decades." But for now, the Court's decision in the Maryland v. King case — regarding whether police can swab your cheeks for DNA during booking — may be functionally irrelevant. The nation doesn't have a genetic-processing apparatus in place to deal with the current overload of DNA samples. There's a massive backlog of biological evidence in crime labs, and efforts to combat that backlog in recent years have failed.
In the case, the majority reasoned your DNA is like a fingerprint — used to maintain identity — rather than a piece of personal information, which would require a search warrant. In a 5-4 decision, the Court maintained in Maryland v. King that it is OK for police to take a swab of a person's cheek cells after that person is booked for a crime, and that it is also OK if that DNA swab implicates the person in custody in a cold case.
In the future, this ruling will be very significant. On the technological horizon are machines that can analyze a sample in 90 minutes. Police will be able to connect the dots between perpetrator and crime with a fluid ease (which frightens some civil-liberties advocates).