On Feb 24, 2012, at 5:43 PM, James A. Donald wrote:

> Truecrypt supports an inner and outer encrypted volume, encryption hidden 
> inside encryption, the intended usage being that you reveal the outer 
> encrypted volume, and refuse to admit the existence of the inner hidden 
> volume.
> 
> To summarize the judgment:  Plausibile deniability, or even not very 
> plausible deniability, means you don't have to produce the key for the inner 
> volume.  The government first has to *prove* that the inner volume exists, 
> and contains something hot.  Only then can it demand the key for the inner 
> volume.
> 
> Defendant revealed, or forensics discovered, the outer volume, which was 
> completely empty.  (Bad idea - you should have something there for plausible 
> deniability, such as legal but mildly embarrassing pornography, and a 
> complete operating system for managing your private business documents, 
> protected by a password that forensics can crack with a dictionary attack)
> 
> Forensics felt that with FIVE TERABYTES of seemingly empty truecrypt drives, 
> there had to be an inner volume, but a strong odor of rat is no substitute 
> for proof.
> 
> (Does there exist FIVE TERABYTES of child pornography in the entire world?)
> 
> Despite forensics suspicions, no one, except the defendant, knows whether 
> there is an inner volume or not, and so the Judge invoked the following 
> precedent.
> 
> http://www.ca11.uscourts.gov/opinions/ops/201112268.pdf
> 
> That producing the key is protected if "conceding the existence, possession, 
> and control of the documents tended to incriminate" the defendant.
> 
> The Judge concluded that in order to compel production of the key, the 
> government has to first prove that specific identified documents exist, and 
> are in the possession and control of the defendant, for example the 
> government would have to prove that the encrypted inner volume existed, was 
> controlled by the defendant, and that he had stored on it a movie called 
> "Lolita does LA", which the police department wanted to watch.

There is no such thing as plausible deniability in a legal context.

Plausible deniability is a term that comes from conspiracy theorists (and like 
many things contains a kernel of truth) to describe a political technique where 
everyone knows what happened but the people who did it just assert that it 
can't be proven, along with a wink and a nudge.

But to get to the specifics here, I've spoken to law enforcement and border 
control people in a country that is not the US, who told me that yeah, they 
know all about TrueCrypt and their assumption is that *everyone* who has 
TrueCrypt has a hidden volume and if they find TrueCrypt they just get straight 
to getting the second password. They said, "We know about that trick, and we're 
not stupid."

I asked them about the case where someone has TrueCrypt but doesn't have a 
hidden volume, what would happen to someone doesn't have one? Their response 
was, "Why would you do a dumb thing like that? The whole point of TrueCrypt is 
to have a hidden volume, and I suppose if you don't have one, you'll be sitting 
in a room by yourself for a long time. We're not *stupid*."

        Jon


_______________________________________________
cryptography mailing list
cryptography@randombit.net
http://lists.randombit.net/mailman/listinfo/cryptography

Reply via email to