The Pennsylvania Supreme Court issued a forceful opinion today holding that the Fifth Amendment to the U.S. Constitution protects individuals from being forced to disclose the passcode to their devices to the police. In a 4-3 decision in Commonwealth v. Davis, the court found that disclosing a password is “testimony” protected by the Fifth Amendment’s privilege against self-incrimination.

EFF filed an amicus brief in Davis, and we were gratified that the court’s opinion closely parallels our arguments. The Fifth Amendment privilege prohibits the government from coercing a confession or forcing a suspect to lead police to incriminating evidence. We argue that unlocking and decrypting a smartphone or computer is the modern equivalent of these forms of self-incrimination.