I'm going to take back some of what I said earlier, as I posted in haste. (Actually thought I was replying to someone else, trying to follow too many threads at once.) 1) A subpoena is a subpoena (literally means "under penalty"), but 2) the enforcement process is somewhat different, and yet, strangely the same. Chelsea Manning is resisting a subpoena in a court (Grand jury) proceeding, directly under the court's authority. The judge, then, can initiate contempt proceedings on his/her own. She's in civil contempt, meaning the court's authority is limited, and the "jail" time is limited to the length of resistance, while the grand jury sits. It's coercive, rather than punitive (criminal contempt).
Barr's contempt is of a congressional subpoena (he's actually not yet been held in contempt, just being contemptuous). Enforcement of a congressional contempt process is more convoluted, and gets to the court differently. First the committee has to refer it, then the House has to vote it (which has not yet happened). THEN, under current procedures, it is referred to the US Attorney for D.C. for enforcement. This is where
Moon's point comes in. In the Holder case, and presumably in Barr's, since the US Attorney is under the Executive, Congress cannot directly force action. In Holder's case, an enforcement action was not pursued (by Obama), but a court did eventually rule that Holder had not violated the subpoena. That's the "Separation of powers" issue. What
I objected to was the
implication that I
perceived that the argument was Congress didn't have the authority to
issue the subpoena as a "separation" issue, rather than the difficulty of enforcing it. The enforcement mechanisms themselves (civil and criminal) are actually the same (jail or fines), but
Congress cannot directly pursue them under current procedures (although they do have inherent procedures they no longer employ), so it falls to the Executive to pursue or or not. (By the way, that can change if Congress passed a law to do so.)
For my previous error/perception, I apologize.