The Electronic Frontier Foundation (EFF) today asked the Supreme Court to overturn a ruling undermining Fifth Amendment protections against self-incrimination and find that constitutional safeguards prevent police from forcing people to provide or use passcodes for their cell phones so officers can access the tremendous amount of private information on phones.

At stake is the fundamental principle that the government can't force people to testify against themselves, including by revealing or using their passcodes.

"When the government demands someone turn over or enter their passcode, it is forcing that person to disclose the contents of their mind and provide a link in a chain of possibly incriminating evidence," said EFF Surveillance Litigation Director Andrew Crocker. "Whenever the government calls on someone to use memorized information to aid in their own prosecution—whether it be a cellphone passcode, a combination to a safe, or even their birthdate—the Fifth Amendment applies."