Forcing a person to use his fingerprint to unlock a cellphone doesn’t violate his constitutional right against self-incrimination, a federal court ruled.

The U.S. District Court for the District of Idaho granted the U.S. government’s bid for a search warrant to compel a child pornography suspect to unlock his phone for a forensic search.

The July 26 decision highlights a split among district courts over whether forcing individuals to use biometric identifiers to unlock their digital devices runs afoul of the U.S. Constitution. No federal circuit court has weighed in on the issue, U.S. District Judge David C. Nye said.

Biometrics and other evolving technologies are prompting courts to reevaluate the constitutional principles that shape the criminal justice system, Matthew S. Adams, a digital privacy attorney at Fox Rothschild LLP in Morristown, N.J., said. Despite the Idaho court’s ruling, courts increasingly are deciding to extend constitutional protections to prevent the compelled decryption of mobile devices, he said.

Under the Fifth Amendment, the government can’t compel a person to give self-incriminating testimony. The Idaho court said that a search warrant to unlock a cell phone wouldn’t violate that amendment because applying a fingerprint to a sensor doesn’t communicate anything, or require a suspect to provide testimonial evidence.

The ruling reversed a magistrate judge’s order denying the government’s search warrant application.

Counsel for the suspect couldn’t immediately be reached for comment. The U.S. attorney’s office represented the government.

The case is In re White Google Pixel 3 XL Cellphone in a Black Incipio Case, D. Idaho, No. 1:19-mj-10441-DCN, 7/26/19.