Last month, I blogged about a California court refusing to force a person to unlock their smartphone. The trend continues.
A Magistrate Judge in Idaho ruled last week that a person cannot be forced to unlock their phone using their fingerprints because it would violate their Fifth Amendment right against self-incrimination (In the Matter of the Search of A White Google Pixel 3 XL cellphone in a black Incipio Case, D. Idaho, 1:19-mj-10441, May 8, 2019 (Order is hosted on Mega.nz)).
To qualify for the Fifth Amendment privilege, a communication must be testimonial, incriminating, and compelled. Forcing a person to provide their fingerprint (or biometrics) to unlock the phone would be testimonial because it would provide compulsory authentication of incriminating information that would aid in the discovery, production or authentication of incriminating evidence. Providing a person's fingerprint would violate the privilege against self-incriminating where the very act of providing their fingerprint (or biometics) may be a compulsory authentication of incriminating information.