Judge: Fifth Amendment doesn't protect encrypted hard drives • Hacker News Board

Re: Judge: Fifth Amendment doesn't protect encrypted hard drives

#51

Post by ctdonath » Tue, Jan 24, 2012, 9:45 PM UTC

It's a variant of what's called "rubber hose cryptology": sometimes it's technologically a lot easier to just beat the password out of someone (smacking the soles of one's feet with a rubber hose apparently being a rather effective technique).

I draw the line using a "rag doll" model. They can compel fingerprints, physical keys, DNA, etc. insofar as they can manipulate your limp unresitive (albeit uncooperative) body to take fingerprints, extract keys from pockets, snip a hair, extract a blood sample, etc. They cannot, however, compel you to act on their behalf and against your own interests - to wit, they cannot demand you speak (type, write, press buttons) words the whole point of which can and will be used against you. A fair argument may be made for compelling you to provide the key/combination to a safe, but only insofar as they CAN tear the safe apart with blowtorches & diamond saws if you don't cooperate. But when it comes to the state's evidence hinging entirely upon the defendant's cooperation, no - that's why we have the 5th Amendment (gov't cannot compel one to testify against self).

Re: Judge: Fifth Amendment doesn't protect encrypted hard drives

#52

Post by rosser » Tue, Jan 24, 2012, 9:45 PM UTC

roc wrote: post #42

gte910h wrote: post #19

Earlier quoted context omitted.

>Even better, there's no proof that you're the one who destroyed the keys: you can't be charged with evidence tempering. The court doesn't really work this way. Just because you cross your fingers when you do something doesn't mean you aren't going to be charged with destruction of evidence.

If an office had a policy of shredding old financial paperwork and that policy was faithfully followed on the day after, say, the COO was whisked away for embezzlement, would it count as evidence tampering? Or to the point: if you use a remotely-stored encrypted volume with a dead man's switch as a day-to-day security policy, would it still be trivial to charge someone for evidence tampering?

AIUI (IANAL, mind), no — or at least it's less likely. It's when you go out of you way to destroy the evidence (and can be demonstrated to have done so) that you're almost certainly facing obstruction charges. If you're just doing the same thing you do every day, it's much harder to establish the intent to destroy inculpatory evidence, which is what would trigger the obstruction charge in the first place.

Second opinion?

Re: Judge: Fifth Amendment doesn't protect encrypted hard drives

#53

Post by showerst » Tue, Jan 24, 2012, 9:50 PM UTC

roc wrote: post #42

gte910h wrote: post #19

Earlier quoted context omitted.

>Even better, there's no proof that you're the one who destroyed the keys: you can't be charged with evidence tempering. The court doesn't really work this way. Just because you cross your fingers when you do something doesn't mean you aren't going to be charged with destruction of evidence.

If an office had a policy of shredding old financial paperwork and that policy was faithfully followed on the day after, say, the COO was whisked away for embezzlement, would it count as evidence tampering? Or to the point: if you use a remotely-stored encrypted volume with a dead man's switch as a day-to-day security policy, would it still be trivial to charge someone for evidence tampering?

The first case is why we have data retention laws.

On the second, I _think_ that in most jursidictions in the US the moment you're arrested you have an impetus not to destroy evidence that probably extends to not allowing evidence to be destroyed by a system that you could trivially prevent.

Putting a system in place where you have to take action to prevent an event is legally similar to a system where you take action to cause an event; in either case you've purposely taken an action that leads to the destruction of evidence.

We'd need a real lawyer to comment, but otherwise I think we'd have already seen things like this for years (even pre-computer)

Re: Judge: Fifth Amendment doesn't protect encrypted hard drives

#54

Post by nknight » Tue, Jan 24, 2012, 10:01 PM UTC

rosser wrote: post #52

roc wrote: post #42

Earlier quoted context omitted.

If an office had a policy of shredding old financial paperwork and that policy was faithfully followed on the day after, say, the COO was whisked away for embezzlement, would it count as evidence tampering? Or to the point: if you use a remotely-stored encrypted volume with a dead man's switch as a day-to-day security policy, would it still be trivial to charge someone for evidence tampering?

AIUI (IANAL, mind), no — or at least it's less likely. It's when you go out of you way to destroy the evidence (and can be demonstrated to have done so) that you're almost certainly facing obstruction charges. If you're just doing the same thing you do every day, it's much harder to establish the intent to destroy inculpatory evidence, which is what would trigger the obstruction charge in the first place. Second opin…

In civil cases, once you know or have reasonable cause to suspect a court case is imminent, you're technically supposed to act to preserve evidence, and not doing so can lead to sanctions, even if the evidence was destroyed as part of routine policy.

I'm less clear on how evidence tampering is dealt with in criminal law.

Re: Judge: Fifth Amendment doesn't protect encrypted hard drives

#55

Post by Czarnian » Tue, Jan 24, 2012, 10:01 PM UTC

simonsarris wrote: post #32

I have question to those who know more about these things: Instead of hidden volumes, wouldn't it be better to have an "under duress" password? The hard drive is encrypted and sensitive folders are identified by the user. When a password is given all contents are decrypted. When a "under duress" password is given the sensitive folders are permanently wiped and all the (remaining, innoculous) contents are decrypted. T…

I was thinking along the same lines, but instead of wiping the file, it changes the password to a randomized 20 character string.

If you're doing anything that risks getting pinched, it's probably better to take the obstruction rap than whatever it is you're being investigated for.

Re: Judge: Fifth Amendment doesn't protect encrypted hard drives

#56

Post by nknight » Tue, Jan 24, 2012, 10:06 PM UTC

underwater wrote: post #47

mattiask wrote: post #39

Earlier quoted context omitted.

What you want to do is to have a password that decrypts the content to something innocently looking. If the encryption program has the feature to both "dual encrypt" and do an ordinary encryption it should be hard to prove anything :) Not sure how you go about doing that algorithmically though so it would resist reverse engineering the program

TrueCrypt does exactly that. The problem is that everyone knows about it; so the police will always suspect there is a second hidden section.

But if you've done it right, they can't prove it. In US law, you can't convict someone criminally because you suspect they're withholding information, you have to be able to prove it beyond reasonable doubt.

Re: Judge: Fifth Amendment doesn't protect encrypted hard drives

#57

Post by rhizome » Tue, Jan 24, 2012, 10:18 PM UTC

ctdonath wrote: post #51

It's a variant of what's called "rubber hose cryptology": sometimes it's technologically a lot easier to just beat the password out of someone (smacking the soles of one's feet with a rubber hose apparently being a rather effective technique). I draw the line using a "rag doll" model. They can compel fingerprints, physical keys, DNA, etc. insofar as they can manipulate your limp unresitive (albeit uncooperative) body…

But when it comes to the state's evidence hinging entirely upon the defendant's cooperation, no - that's why we have the 5th Amendment (gov't cannot compel one to testify against self).

And really, doesn't that mean it (whatever is obscured by a lack of cooperation) shouldn't be considered a crime? Kind of by definition?

Re: Judge: Fifth Amendment doesn't protect encrypted hard drives

#58

Post by baddox » Tue, Jan 24, 2012, 10:19 PM UTC

sp332 wrote: post #7

ge0rg wrote: post #3

Earlier quoted context omitted.

Yes. The term for that is plausible deniability. It is implemented (probably among others) in truecrypt: http://www.truecrypt.org/docs/?s=plausible-deniability

Plausible deniability is a much larger concept than that. Also if they know you're using Truecrypt, the "deniability" of the existence of a 2nd (or 3rd or 4th) OS goes down significantly.

The deniability doesn't diminish at all. You can even testify in court that the drive is encrypted using TrueCrypt and that TrueCrypt has plausible deniability. The whole point of TrueCrypt's plausible deniability is even when you know about the feature, you simply can't mathematically prove whether or not it's being used.

Re: Judge: Fifth Amendment doesn't protect encrypted hard drives

#59

Post by fab13n » Tue, Jan 24, 2012, 10:20 PM UTC

gte910h wrote: post #19

fab13n wrote: post #12

To counter this, you need an encryption method with these properties: - you can be banned or self-banned, irrevocably, from accessing your data; - you can prove to the judge that you can't access your data; - even with full forensic copies of your disk, you can't be un-banned. You can do that by having part(s) of the key on server(s) online. Give yourself, a couple of trusted friends and optionally a script, the abil…

>Even better, there's no proof that you're the one who destroyed the keys: you can't be charged with evidence tempering. The court doesn't really work this way. Just because you cross your fingers when you do something doesn't mean you aren't going to be charged with destruction of evidence.

The way courts generally work, they need a proof you've done something wrong to condemn you. If there are a dozen friends who had the wiping rights to your keys, and they knew you'd been arrested, any of them could have decided to wipe the key, just in case.

Unless the judge can prove who did it, he can't condemn the 13 (12+you) of you because one of you did something wrong. Besides, the 12 innocents don't know who did it either, so they can't snitch.

It requires the wiping procedure to be impractically hard to trace back, but that can be done.

Re: Judge: Fifth Amendment doesn't protect encrypted hard drives

#60

Post by repsilat » Tue, Jan 24, 2012, 10:29 PM UTC

tedunangst wrote: post #33

simonsarris wrote: post #32

I have question to those who know more about these things: Instead of hidden volumes, wouldn't it be better to have an "under duress" password? The hard drive is encrypted and sensitive folders are identified by the user. When a password is given all contents are decrypted. When a "under duress" password is given the sensitive folders are permanently wiped and all the (remaining, innoculous) contents are decrypted. T…

Then they restore the hard drive from the cloned image they made before entering the password and ask you once more for the password. This time, with feeling.

There might be a market for keeping your keys on some service "out there". Boot your computer, type in your password, your computer sends the password to the key service. If the password is correct they send back the key, if the password is the destruct codes they delete the key.

No amount of hard-drive cloning will stop this. Paired with some other optional measures ("we delete the password unless you send an email every week" etc) and it's almost foolproof. You might still have a hard time arguing against destruction of evidence, though. I guess if your "don't delete the keys" email was "Please delete my encryption keys" you could be completely honest and they wouldn't believe you, resulting in your keys being deleted despite your complete cooperation.