Maryland v. King
Citation
569 U.S. 435 (2013). Supreme Court of the United States.
Facts
Maryland law authorized police to collect a DNA sample via cheek swab from individuals arrested (not yet convicted) for serious offenses. Alonzo King was arrested for assault and his DNA was entered into a database, which matched an unsolved rape case. He was convicted of rape and challenged the DNA collection as an unreasonable warrantless search.
Issue
Does the Fourth Amendment permit law enforcement to collect a DNA sample from an individual upon arrest for a serious offense, before any conviction?
Holding
The Court upheld the DNA collection as a reasonable search under the Fourth Amendment, applying a balancing test: the government’s substantial interest in identifying arrestees (and solving cold cases) outweighed the minimal physical intrusion of a cheek swab.
Rule / Doctrine
The Fourth Amendment permits DNA collection at arrest for serious crimes without a warrant or individualized suspicion. The government interest — identifying who has been arrested, ensuring proper release decisions, and solving outstanding crimes — is significant. The intrusion — a cheek swab — is minimal. The Court analogized DNA booking to fingerprinting incident to arrest, a long-accepted practice.
Significance
King is controversial because the Court’s identification rationale was disputed — DNA results were not available for months and were not actually used for booking identification. Dissent (Scalia) argued DNA collection was purely investigative, not identificatory. The case raises broad questions about genetic privacy, the scope of “identification” searches, and the permissibility of suspicionless investigative searches tied to arrest status.