Judge rules against forcing suspects to unlock phones with Touch ID or Face ID

Using Touch ID to unlock an iPhone

US Magistrate Judge Virginia Demarchi, of the Northern District of California, has ruled that unlocking a device such as an iPhone is "inherently testimonial." She said it amounted to forcing incriminating testimony from an individual.

"Here, compelling an individual who is a target of the investigation to use his or her finger or face to unlock a device represents incriminating testimony within the meaning of the Fifth Amendment," she said. Judge Demarchi also addressed the fact that law enforcement bodies are now repeatedly arguing a case that such unlocking is required.

"Several magistrate judges and district court judges across the country, as well as a few state courts, have recently addressed the specific question of whether compelled application of a biometric feature to an electronic device is a testimonial communication," said Judge Demarchi.

"This Court agrees with those courts," she continued, "that have concluded that requiring an individual to use a biometric feature to unlock an electronic device so that its contents may be accessed is an act of production that is inherently testimonial in the context of a criminal investigation."

In her ruling, Judge Demarchi explained that such unlocking using biometrics implies certain points that are the equivalent of providing testimony.

"Because it amounts to an assertion of fact that the individual has the ability to unlock the device," she said, "which in turn makes it more like that the individual locked the device and put the material sought by the warrant on the device."

Judge Demarchi's follows a similar case in Idaho in May this year and another California ruling in January.

However, also in May this year, a Massachusetts judge did grant a warrant to allow agents of the Bureau of Alcohol, Tobacco and Firearms to compel a suspect to use Touch ID to unlock his iPhone.