AFAIK, it's still not settled whether cryptographic keys/passwords/passphrases can be subpoena'd. Existing case law from physical security distinguishes between

AFAIK, it's still not settled whether cryptographic keys/passwords/passphrases can be subpoena'd. Existing case law from physical security distinguishes between keys--like the one to your door or a cabinet--from combinations--like those to a safe. The state can legally demand the former, as the law views them as physical evidence as any other that may be rightly relinquished with a proper warrant. The latter, however, are the contents of one's mind, and as such requiring their divulgence runs afowl of 1st amendment protection of free speech and/or 4th amendment protection against self-incrimination. To me, it seems obvious that encryption 'keys' are much more like 'combinations', and were only called 'keys' as a word play (like many concepts in IT). Prosecutors, however, see that word and go "hey, wait a second, we're entitled to those!!"