Earlier quoted context omitted.
Since the courts decided you have to use your fingerprint to unlock your phone (because they decided that's not giving up your password and they can't compel you to give up your password), what if you use your fingerprint to wipe your phone? But you don't tell anyone ahead of time when they force you to use it. I'm sure you'd be arrested at the least. I can't be the only person who has thought of this.
This would still be destruction of evidence - virtually your only defense against that would be if it was not triggered by you .
(Common sense tells me that the accusation might make sense both in cases in which the accused knows about a crime and in cases in which the accused knows about a police investigation, even in the absence of a crime, but deleting nude photographs to stop a customs officer from seeing them, for a random example, would that be a crime?)