But what if the safe had documents in it which was written in a language that only you know? Is there any circumstances where you could be compelled to translate them?
Some bookkepers for crime organizations have from time to time used their own notation to keep the books. Typically, they have not been sophisticated enough to hide malfeasance, in addition, the shadiness of it is often enough evidence of wrongdoing, or at least leads to forensic accounting which reveals tax evasion.