To add to this spending some time in custody is inconvenient, but losing your rights being convicted of something you didn’t even do is more inconvenient. You think you know what to say until you say the wrong thing and start digging a hole.

This is good to know, but adds an additional step to simply requiring a passcode to unlock on screen lock.

Just the act of refusing makes the act of seizing your phone legal or not. If you legally give them your phone by your own will, they are able to use all evidence they find in the courts. If you deny to give them your phone, and they seize it anyways and access it you have a valid path to throw the evidence they discover out as an illegal search and seizure of your property. I’m not a lawyer but that is the general thought process on denying them access to your property.

Edit: Just want to say this mostly pretains to United States law and similar legal structures. This advice is not applicable everywhere and you should research your countries rights and legal protections.

I personally rather trust that my device isn’t able to be unlocked without my permission, rather than hope I am able to do some action to disable it in certain situations. The availability of such features is nice, but I would assume I would be incapable of performing such actions in the moment.

My other thought is, how guilty is one perceived if they immediately attempt to lock their phones in such a matter, by a jury of their peers? I rather go the deniability route of I didn’t want to share my passcode vs I locked my phone down cause the cops were grabbing me.

To add to this, don’t use bio-metrics to lock your devices. Cops will “accidentally” use these to unlock devices when they are forcibly seized.