Would this be treated the same way?
Are you essentially asking if bitcoin has ownership?
I would assume that using someone else's credentials (wallet private key) without permission to make changes to a system (the bitcoin blockchain) is in itself illegal, yes.
IANAL.
They are clearly associated with the hack, but that can be tacked on after further investigation and cross-examination. The money laundering is an easier opening target.
Of course, correctly guessing a 256-bit random private key is exceedingly unlikely, though if they key is based on a lower-entropy password (a "brain wallet") then the odds of a correct guess improve dramatically.
There is this ownerless software running.
I don’t see it as theft.
And even if it weren't that's no different than guessing someone's bank account number and paying for purchases that way. Its still someone else's money and its still stealing.
We don't have to guess. The CFAA refers to unauthorized access to computers, not "systems". The Bitcoin network is not a computer, and someone posting a transaction signed with some key, however that key was obtained, is using the network as intended and not accessing either the Bitcoin network as a whole or the individual computers comprising the Bitcoin network in an unauthorized manner.
> And even if it weren't that's no different than guessing someone's bank account number and paying for purchases that way.
It is different, because in that scenario you're claiming to be the designated account owner, a specific legal person authorized by contract to direct the bank to pay money from that account—not just someone who knows the account number. You generally have to sign a statement to that effect in addition to providing the account details. If you aren't the account holder then you're committing fraud. (Though practically speaking it's really a bit ridiculous that merely knowing the account number—something printed on every check and hardly a closely-held secret—is considered sufficient to set up a direct debit.)
By design, Bitcoin doesn't care about your real-world identity; it only cares about whether you know the private key.
> Its still someone else's money and its still stealing.
Wrong on both counts. Bitcoins are an abstract concept, much like points in a game. They are governed by voluntary consensus among Bitcoin users according to a particular specialized system of rules, and not your private property. In short, they're "yours" only as long as the network says they're "yours". If other Bitcoin users stop recognizing those bitcoins as "yours" for whatever reason—a blockchain fork, a change in the consensus rules, someone else guessing your private key and spending them—you have no legal recourse. There are no physical goods involved which you could sue to have returned to you, and no legally-binding contracts between you and any other participants in the Bitcoin network which you could claim were breached by the change.