Former prisoner on federal supervised release might have reasonably believed that he was compelled by the terms of the supervised release to unlock his phone and answer the questions truthfully, so while the information can be used to revoke the supervised release, the 5A right to silence was invoked by operation of law, meaning that the information cannot be used in a subsequent prosecution.
Remand for consideration of inevitable discovery exception.
Dissent:
Deft's invocation wasn't automatic, since his subjective belief wasn't reasonable in light of the prevailing law.