> The lawsuit asks the court to declare that Trump is in violation of the emoluments clause. Even if he is, though, it would be up to Congress to decide whether that merits impeaching him and removing him from office — and Republicans in Congress so far have been reluctant to look into Trump’s break with tradition on ethical issues.

If SCOTUS were to rule for the plaintiffs in this case, the Congress would be in a much more difficult spot. Right now they can dismiss it all as "he said she said" and "not really illegal". But if there's a SCOTUS ruling that the president is in violation of the Constitution, and they don't impeach, they'd basically be saying that either they don't care about the Constitution, or they don't care about SCOTUS. Either would cause a major constitutional crisis with unclear consequences.

I don't know. I think Trump could literally say that he doesn't care about SCOTUS and it would be unlikely to be the wildest thing he said that day. A Republican majority Congress could definitely ignore a SCOTUS ruling.

I'm not saying that they can't do it. I wouldn't even be particularly surprised if Trump does it - he is, allegedly, a big fan of Andrew Jackson, the only president to date in US history who openly defied the Supreme Court ("John Marshall has made his decision, now let him enforce it").

I would be somewhat surprised if the Congress ended up doing it, but seeing how spineless they already are wrt Trump even where he contradicts them, not super surprised.

My point, rather, is that, should such a thing happen, it would be a bona fide constitutional crisis. If two branches of government are openly in defiance of parts of the Constitution, it becomes a free for everyone else, as well. Secession would suddenly be on the table for real - after all, the Constitution is what makes the Union, so if the Constitution is no longer the supreme law of the land, then the states could reasonably argue that they aren't bound to the Union in any sensible way. Or they could simply state that per the Emoluments Clause, they consider the president illegitimate from there on, and so no EO and no act of Congress signed by him has force of law on their territory. Or even invoke the 9th and the 10th Amendments in a full-on literalist vein (stealing the book from fringe factions of the right), and just claim that the feds simply don't have most powers that they claim as well.

This is all very far-fetched, but in the event of an open defiance of SCOTUS by the other two branches, we'd already be in the realm of far-fetched things, so the impossible becomes possible, and unlikely becomes probable.

But it would mean Trump would be serving at the mercy of Congress, and at the mercy of maintaining a Republican majority, which could have substantial effects on policy in itself even if he's never impeached.