If they have a warrant, they can force you under threat of legal action if you don't comply. If they don't have a warrant, you can claim the 4th. If they try to get you to divulge the password/code/secret, you plead the 5th. If you let them in, well... Politely tell them they are no longer welcome. Please leave. If they don't comply, they are trespassing (unless they have a warrant, in which case none of the above applies and you're probably going to jail, wear clean underwear).

I have to wonder how much of this goes on without a warrant, just pressuring people into it.

News articles suggests this happens a lot at the borders or during customs.

A border crossing is an entirely different realm where these rules do not apply.

Yeah. I believe they can look in your phone.

See also, the 100-mile "constitution free zone" in which around 2/3rds of the country live.

https://www.yesmagazine.org/social-justice/2018/03/23/two-th...

For what it's worth you'll still be charged with destruction and/or obstruction even if you warn them.

Interesting, and surprising. Is there case history and purported rationale on that?

Why is that surprising? The 5th isn't some sort of blanket gotcha, it's just there to curtail abuse.

There's a huge difference between "get out of the way" and "compelled to help".

Right, but that doesn't cover "and I booby trapped it". Why wouldn't you be open to charges in that case? Obstruction, destruction of evidence, contempt of court - such mechanisms exist in part to cover such cases.

I think there's a case to be made that if the contents contain a booby trap before the warrant is issued and executed, they found what was inside, a booby trap was inside. Similar to a canary, an action that causes destruction of evidence deliberately after the warrant was issued is not the same as a system in place beforehand that performs the action automatically in every case without input from the user. This obviously doesn't apply to say a passcode that wipes evidence as that requires deliberate action, but it would apply to something like wiping if the wrong passcode is entered 3 times.

Exactly. Intent also seems like it should matter. If your intent was "destroy evidence if the police comes knocking" that's one thing. If your intent was "have an extra secure safe to protect my secrets from anyone who might steal them" and you made that decision without knowledge of any warrant, that seems like it ought to be fine.

It's an interesting area, the 5th is actually really narrow (and of course other jurisdictions have something else). It's not obvious what can be compelled; e.g. it wouldn't seem like a court ordering you to defeat such a measure would run afoul of 5th, but maybe something else.

I'm not sure it's directly applicable, but courts have repeatedly ruled that you can't booby-trap your own property; I'm not quite sure this applies to, say, [non-explosively] erasing a USB drive by entering a decoy PIN.

https://www.hecklawoffices.com/blog/2020/11/its-illegal-for-...

Yeah we aren't talking about land mines here, just devices that destroy the owner's property, and more specifically software systems that destroy information. It is well established that weapons that harm people automatically are illegal.

I have been curious about when/where destruction of evidence takes place. Presumably during the crime, the perpetrator does their best to hide the evidence.

Does it only become destruction after you have been informed the police are interested in you? What if you do it before a warrant is issued? What if your device will self destruct if a password is not entered every N days and you withhold that information?