You should research this. A judge can order you to provide the passphrase to decrypt the storage that contains the bitcoin wallet if it is a foregone conclusion that there is one on there, and if you refuse then you can be held in contempt and jailed until you do provide it. There is no time limit to contempt of court imprisonment because you are free to stop being in contempt whenever you choose. You will have a very hard time getting an appeals court to issue a mandamus order to the judge that jailed you for contempt, and by "hard" I mean "impossible".