The justices return to cellphones and the Fourth Amendment: In Plain English

In 1976, in United States v. Miller, the Supreme Court ruled that the bank records of a man accused of running an illegal whiskey-distilling operation were not obtained in violation of the Fourth Amendment, even though law-enforcement officials did not have a warrant, because the bank records contained “only information voluntarily conveyed to the banks and exposed to their employees in the ordinary course of business.” Three years later, in Smith v. Maryland, the justices ruled that no Fourth Amendment violation had occurred when, without a warrant and at the request of the police, the phone company installed a device to record all of the phone numbers that a robbery suspect called from his home, leading to his arrest.