That is a great question... I am not sure, I think the better question is how can you make a setup where you cannot give them your keys but also prove to them that no matter what they do you cannot give them. For example with a geographically distributed multisig or similar setup, but how do you convince them that you really cannot get the keys easily in that moment..?
Discussion
I think that’s the best security, but it depends a lot on the criminal. He probably won’t understand, and if he does, he might not believe it. Maybe if he’s smart and knows how to talk about it properly, but it’s hard to say
It's logically impossible to convince others that you don't know something, unfortunately.
The best solution is to have a provable delay during which the unlocking of the funds from cold storage can be reversed. First, that is obviously not a 100% solution against attackers willing and able to keep their threat active against you for a *long* time, and second, it really needs covenants to not be a very inconvenient construction.