1. Not every vocal Utterance qualifies as Testimony, and the only person who gets to self-identify with an encryption key is Whitfield Diffie, and that rule only applies after 3 bong hits -OR- when he's doing Salvia with Ron Rivest as his sitter. Your weasel card-skimming ass ain't no Whitfield Diffie.
2. If you leak enough inculpatory evidence outside your encrypted hard drive, such that the police are now holding a warrant for searching inside your encrypted hard drive, the jig is up, son! Shouldn't have leaked all that other guilt-stench, and should have plausibly-deniably deleted that evidence.