I'm glad you didn't take offense to me making reference to the fallacy as I appreciate our conversation and wasn't sure how else to express that thought.

If you haven't done so, check out the source document for the article as Arstechnica didn't include some important details (and the headline "Man jailed indefinitely for refusing to decrypt hard drives loses appeal" talks past what is actually happening): https://arstechnica.com/wp-content/uploads/2017/03/rawlsopin...

> ...but what if an ISP reports that files with those hashes have been downloaded by a particular IP address? ... but can't find the files the ISP says should be there.

I think this case is particular due to the lack of breaks in the chain. In your hypothetical, law enforcement and the prosecution have _vastly less information_ than in this actual case.

Law enforcement knew the path from a remote source, to (presumably dhcp lease based) ISP records, to the laptop that accessed the content (known to be the defendant's), to checksums in logs matching a physical drive (also known to be the defendant's). Coupled with other evidence, the defendant frustrating the process by pretending to no longer know the decryption phrase, and partial admissions of guilt by the defendant, this is a vast distance than a hypothetical case of "someone from this IP address downloaded Game of Thrones Season 1 from bittorrent, so hand over anything that can store bytes" (to use a far less disgusting crime to help keep emotion away from the discussion).

> Based on this precedent, I think another judge could find reasonable cause to compel in that scenario.

Luckily, the US justice system is built on nuance; this case wouldn't hold up as a generalizable excuse to compel decryption -- which is why they're invoking the foregone conclusion rule to secure the production of evidence based on the enormity of the other factors.

> In this hypothetical case, though, what if LE found OTHER files of child pornography? Would they be admissable?

I honestly don't know. In this case, the defendant is refusing to provide (multiple pieces of) evidence that is known to exist by checksum and direct file path.

> Alternatively, if they found other material (e.g, bomb-making), could it be used against him in a separate case?

Having information on how to construct a bomb is not illegal, any more than getting a degree in chemistry is illegal, but plotting to kill people with a bomb is legally actionable.

> I'm not sure I trust the government in either one of these situations.

I agree with you, but on a different shade of the argument. I'm suspicious that the ecosystem of justice is built on securing convictions as opposed to seeking objective truths. In this case, I support the government/court based on the information I have.

> As with so many other of the Constitutional protections of the Bill of Rights, they've slowly been chipped away in precisely these kinds of legal "corner cases."

I don't know which other cases to which you're referring, but the argument to be made here is that this isn't a corner case. This is having mathematical certainty that the defendant has evidence and is refusing to hand it over.

> Sue me for being paranoid.

No law against being paranoid :)

> but it's extraordinarily clear that shouldn't be happening in the first place, according The Constitution.

Actual question: where in the constitution is this clearly stated?