Bloomberg Law
Nov. 25, 2019, 9:31 PM

Forced Phone Fingerprint Unlock is Constitutional, Judge Says

Sara Merken
Sara Merken

A man must use his fingerprints to attempt to unlock his phone, an Illinois federal district court ordered in signing a search warrant, finding that the request does not violate the Fourth or Fifth Amendment.

The ruling adds to a growing list of disparate court opinions about whether forcing individuals to open their cell phones with biometric identifiers violates the Fifth Amendment’s right against self-incrimination. Federal and state judges across the country have come down on different sides of the constitutional question.

The government’s warrant application established probable cause to believe there was evidence of a crime on defendant Anthony Barrera’s cell phone under the Fourth Amendment, the U.S. District Court for the Northern District of Illinois in signing the search warrant application. The Nov. 22 ruling doesn’t specify what government agency wanted to access Barrera’s information.

“Compelling an individual to scan their biometrics, and in particular their fingerprints, to unlock a smartphone device neither violates the Fourth nor Fifth Amendment,” Magistrate Judge Sunil R. Harjani wrote. The warrant includes the authority to compel Barrera to press his fingers and thumbs on the iPhone’s home button in an attempt to unlock it.

Barrera was charged with unlawfully possessing a firearm after being convicted of another felony, and the evidence establishing he committed the crime included a video showing him with a gun, the court said. The government alleged that he made online threats to an informant through Snapchat, and the government wants to search the phone to develop evidence of the alleged threats, according to the opinion.

Compelling Barrera to use his fingerprint to unlock a device is not self-incriminating testimony under the Fifth Amendment, Harjani said. The procedure of using biometrics to unlock a phone is “more akin to a key than a passcode combination,” and that the procedure is a physical act, he said.

The court also found that the “implicit inference from the biometric unlock procedure, that the individual forced to unlock had some point accessed the phone to program his or her fingerprint, is not sufficient to convert the act to testimonial,” Harjani said.

The case is United States v. Barrera, 2019 BL 451168, N.D. Ill., 19 CR 439, 11/22/19.

To contact the reporter on this story: Sara Merken in Washington at

To contact the editor responsible for this story: John Hughes at; Keith Perine at