plausibly deniable

[Robert J. Hansen]

On 7/22/2010 10:43 PM, Ted Smith wrote:
>> Thanks to the deniable encryption features of TrueCrypt, there is no way
>> to account for all the data.  Is that empty space in your container, or
>> is there a small hidden container that you're not confessing?
>> Ultimately, you can't make the interrogation stop *even if you confess
>> all the information the interrogator wants* -- because the interrogator
>> might (reasonably!) think you're holding out.
> 
> An interrogator as described in this thread is a movie plot threat. In
> reality, nobody is going to torture you for your key...

The point is not about torture.  The point is about interrogation.

Imagine this scenario: you've been sending innocuous encrypted traffic
to a correspondent.  Unknown to you, your correspondent is involved in
drug trafficking.  You're arrested on suspicion of drug trafficking and
brought to speak with the prosecutor.  You happily decrypt your
innocuous emails.  The prosecutor now asks to see the contents of your
TrueCrypt container.  You comply, since there's nothing illegal in there
-- just your tax records (which the prosecutor already has anyway).

The prosecutor tells you to produce the contents of the hidden
container.  "But I don't have an encrypted container!"  Prove it.  "I
can't!"  Then I guess we have no choice but to keep our investigation on
you open, take your life apart one bit at a time, drag your reputation
through the mud with our investigation, and cause you to spend untold
tens of thousands of dollars on legal fees.  Then in six months if we
can't find anything, maybe we'll drop it.  Or you can prove to me that
you don't have an encrypted container.  Your choice.