I'm not a lawyer. However, the amicus brief[1] is pretty good reading and addresses your scenario above with a locked box, vault or safe. In those instances, th

I'm not a lawyer. However, the amicus brief[1] is pretty good reading and addresses your scenario above with a locked box, vault or safe. In those instances, the "content" doesn't change (hence the decryption argument doesn't apply here), but the method by which the lockbox is secured greatly matters (page 13 of the brief): "As the Supreme Court noted in Hubbell, the compelled entry of a safe’s combination is testimonial because it requires the compelled use of the “contents of [an individual’s] own mind” and is thus within the Fifth Amendment’s privilege. [...] Meanwhile, the compelled production of a lockbox’s key is not testimonial, because it involves “a mere physical act”." Thus, biometric data (i.e. the act of placing your face or finger near/on the device to unlock) could be construed as a "mere physical act" as referenced in the U.S. vs. Hubbell Supreme Court case[2]. [1] https://www.eff.org/document/us-v-mitchell-eff-and-aclu-amicus-brief https://www.eff.org/document/us-v-mitchell-eff-and-aclu-amic... [2] https://en.wikipedia.org/wiki/United_States_v._Hubbell https://en.wikipedia.org/wiki/United_States_v._Hubbell