To me, this whole thing smells of the classic tactic of telling the guy, "We know you're guilty; just confess, and we'll go easy on you." Which, of course, is a lie.
So I am of the opposite opinion. If the hash information isn't enough to try him with, then I'd rather he go free, than set a precedent that it's acceptable for a court to compel someone to decrypt information because someone in law enforcement just "knows" the evidence is there. Because once this order is allowed to stand, the level of certainty required to compel decryption is going to continually be lowered.
So I am of the opposite opinion. If the hash information isn't enough to try him with, then I'd rather he go free, than set a precedent that it's acceptable for a court to compel someone to decrypt information because someone in law enforcement just "knows" the evidence is there. Because once this order is allowed to stand, the level of certainty required to compel decryption is going to continually be lowered.