Decius wrote:

Does encrypting Internet communications create a reasonable expectation of privacy in their contents, triggering Fourth Amendment protection? At first blush, it seems that the answer must be yes: A reasonable person would surely expect that encrypted communications will remain private. In this paper, Professor Kerr explains why this intuitive answer is entirely wrong: Encrypting communications cannot create a reasonable expectation of privacy. The reason is that the Fourth Amendment regulates access, not understanding: no matter how unlikely it is that the government will successfully decrypt ciphertext, the Fourth Amendment offers no protection if it succeeds. As a result, the government does not need a search warrant to decrypt encrypted communications.

If you put an encrypted file in a password protected stuffit file, would that give the file fourth ammenment protection from the access needed to open the stuffit file and actual protection from the encryption? If you are handed a warrant demanding "access" to some file, you should not be required to surrender your encrypted key as well because "understanding" is not required by law, right? Somehow I think that the analogy doesn't hold water. Because "understanding" requires forging an algorithmic key to break apart an encrypted framework, I think that access is required for understanding. If you wrote a message on a piece of paper and folded it in on itself and sealed it with glue, this would qualify as an envelope. Encryption mathmatically "folds" communication and seals it with a key. There is no closer digitaly secure envelope analogy one can make. If one were to contend that digital communications should be a valid and useful method to communicate, the envelope is needed to assure viability for most important uses. If you can't count on encryption for this, what can you count on?

RE: The Volokh Conspiracy - Can Encryption create an expectation of privacy