Courts have ruled that providing a password to decrypt something is not in itself testimony and isn't protected by the 5th amendment. Judges can certainly hold

Courts have ruled that providing a password to decrypt something is not in itself testimony and isn't protected by the 5th amendment. Judges can certainly hold you in court indefinitely on a contempt of court charge as well. Considering the nature of the charges that this typically comes up in (see Francis Rawls) I wouldn't count on trying to make it a civil rights issue doing much in your favor.