That's the theory. In practice police can get away with pretty much anything, and if you make it to the point where a judge is listening to you, he/she won't be sympathetic.
You've seen the videos where the idiot cop didn't realize his camera was on and filmed himself placing drugs? This didn't just happen once.
Do you have any evidence for this? Courts routinely suppress evidence.
> and filmed himself placing drugs?
I saw the video; it's bad and it's an injustice. No one was convicted of a crime in this case, though I suspect others likely plead guilty in similar circumstances given their incentives in our current system.
But why does that affects your decision to lock your phone? Are you worried police are going to illegally compel a fingerprint from you and then put something on your phone?
Of course I can't comment on all judges, but in my few interactions with them, the court sides with the police. Call it an anecdote if you want, but "citation needed" comments wear thin.
> But why does that affects your decision to lock your phone? Are you worried police are going to illegally compel a fingerprint from you and then put something on your phone?
I worry about every interaction with a police officer. They are the single biggest threat I ever run into.