The United States Supreme Court unanimously ruled on Monday that police officers must obtain a search warrant before attaching a GPS tracker device to the vehicle of a suspect. The decision, which is celebrated by advocates of privacy rights, is said to be one of the first major cases determining how constitutional privacy rights flesh out in an age of digital technology.

The decision upholds that of a federal appeals court in Washington, which threw out a drug conviction due to the fact that police obtained evidence of the crime by placing a GPS tracker on the suspect’s vehicle without first obtaining a valid warrant. The warrant had apparently been obtained in the District of Columbia, but was not installed until it was expired and the vehicle was parked in Maryland. Police didn’t renew the warrant or get a valid one in Maryland.

Although the court unanimously agreed in its decision, there was a divide over the reasoning for the decision. The majority of the justices opined that the Fourth Amendment protection against unreasonable searches and seizures extends to private property like automobiles.

Justice Alito said that the search was a violation of the suspect’s “reasonable expectation of privacy,” and said that a property-based approach was too narrow to deal adequately protect privacy rights from the potential impositions of modern technology.

The decision is a welcome one, and good news for all privacy advocates. Unreasonable searches and seizures are a major way criminal defendants are able to keep certain evidence out of the courtroom. Police officers need to be held accountable for following the proper standards of law.

Source: Wall Street Journal, “High Court Backs Privacy Rights in GPS Case,” Jess Bravin, January 23, 2011.