This past week, the United States Supreme Court heard oral argument in Carpenter v. United States, a case that goes to the heart of the government's power to track private individual behavior without a warrant. Timothy Carpenter and his henchmen had engaged in a series of armed robberies in Michigan and Ohio that led to his conviction for up to 116 years in prison. In his opinion, Judge Raymond Kethledge of the Sixth Circuit correctly observed that the Fourth Amendment's protection against unreasonable searches and seizures “has long recognized a distinction between the content of a communication and the information necessary to convey it. Content, per this distinction, is protected under the Fourth Amendment, but routing information is not.”
Accordingly, Kethledge let the government introduce into evidence the business records from the defendants' wireless carriers that placed the defendants at or near the scene of several violent robberies. Alone, that evidence could never support a conviction for armed robbery, but its value lies in contravening the defendants' alibi that they were elsewhere at the time.