I would say that police use ‘violence’ to acquire what they want all the time and the de-encryption of data is potentially no different. It would be a foolish mistake to ignore the State’s monopoly on force. While there is certainly a difference between the threat of violence and the application of violence, it is more the general ability of the State to utilize force for those aims society has agreed are within the State’s remit. While it may not be ‘violence’ per se, detention and deprivation of freedom are certainly applications of force and said detention is often preceded by actual violence to secure an individual for that detention. I am certain that periods of detention are enough to make a decent percentage of even the most principled individuals turn over their data. It is clear game theory, if I can be held for multiple rounds of incarcerations while keeping the data, but I can reasonably expect some determinate sentence from something in the data, is the trade-off worth it? Law enforcement doesn’t need the clarity of law, individuals need clarity of law to restrict those officers.

It's called rubber hose cryptanalysis for a reason. Holding you in prison at all (let alone indefinitely) requires violence. Violence is applied to get the defendant to reveal their decryption keys.

> attempting to hide or destroy their books

This is precisely why "Obstruction of Justice" is a criminal offense with severe penalties available. The question then becomes: is deliberately encrypting and refusing to provide access to those books obstruction?

I know the folks here would argue otherwise, but IMHO it's not at all a clear argument legally. The original reasoning behind the fifth amendment was that without that protection the government would be tempted to use coercive tactics to induce a false confession. It's designed to prevent the torture of accused witches, not to be a literal get-out-of-jail-free card for crypto nuts.

> is deliberately encrypting and refusing to provide access to those books obstruction?

Since email deletion policies aren't obstruction until you're told to suspend them, there's no way an encryption policy is obstruction.

> to be a literal get-out-of-jail-free card for crypto nuts

Pff. It's not like simply not writing things down is a get out of jail free card.

To not encrypt your books for a business would be negligence; I assume you leave all your valuable information as clear text for the convenience of future investigations?

I wrote "is deliberately encrypting and refusing to provide access to those books obstruction?". And again, I don't think that argument is anywhere near as clear cut as you want it to be. The fifth amendment, again, is intended to prevent torture, not to prevent the collection of evidence in a criminal investigation.

So technicalities like you're invoking (is refusing to do something "obstruction" or not?) need to be balanced against technicalities on the other side (is providing a decryption key "testimony"?). And when courts have had to make decisions like this they've almost always done it by splitting the difference in some way instead of finding an absolute interpretation on one side or the other.

Oh, after the fact? I would agree that is definitely obstruction. Before the fact - maybe for business, but not for personal. 5th amendment is to protect against forcing someone to provide evidence against themselves whether that is through torture or coercion, it does not matter.

But again you face the technicality: is providing access to already-existing documents "testimony" in the sense the fifth amendment intends? You can't torture someone into producing documents that don't exist, obviously! Nor is going to jail for obstruction of justice "coercion", effectively by definition.

I'm not saying I disagree with you in principle, I'm saying that very reasonable courts might not. This isn't a cut and dry argument, at all.

> I'm pretty sure it's relatively simple for police to break into offices and take financial records. I would imagine it happens relatively often, because simply asking a suspect to give up their books seems more likely to result in them attempting to hide or destroy their books.

No, this requires a warrant in the US for it to be lawfully used as evidence.

It's worth noting that the defendant in question was told to unencrypt the devices by the courts, which is pretty much in effect the same thing as a warrant, so it's not as if the government was torturing him to decrypt the data; the court had already decided it was material evidence in a case.