Senate Republicans appear ready to take the gloves off against Donald Trump when it comes to the Department of Justice, and not just to protect Jeff Sessions. Lindsey Graham issued a “red line” on Trump’s real target in the Sessions feud, warning that any attempt to remove Special Counsel Robert Mueller could be “the beginning of the end of the Trump presidency,” absent an independent finding of malpractice or abuse of power. Graham announced that he would introduce legislation soon to be sure that “a check and balance” exists:

“Any effort to go after Mueller could be the beginning of the end of the Trump presidency unless Mueller did something wrong,” Graham told reporters on Capitol Hill, where he outlined plans to introduce legislation next week that would move to block any Trump attempts to fire Mueller.

Graham said his bill — which he promised would have Republican support and “all the Democrats” — would mandate that any special counsel established to investigate either a president or his staff can’t be fired “unless you have judicial review of the firing.”

“We need a check and balance here,” Graham said.

What a difference two months make. In May, after the firing of James Comey and a slew of Trump comments on the Russia probe made the appointment of a special counsel inevitable, Graham cautioned against the move. The investigation of Russian influence on the 2016 election properly belonged to Congress, Graham argued, although it might be appropriate in this case. However, the criminal probe would make it more difficult to get witnesses to testify before Congressional committees, Graham predicted, and would leave those committees “knocked out of the game.”

The antics of the president has changed all of those incentives. Normally, Republicans would want to press for controls over the actions of the special counsel, which is itself a position largely outside of normal checks and balances. The history of such officials has proven in most cases why checks and balances are necessary for independent investigations, as they routinely expand into territory far outside their mandate. The willingness of Graham — and likely a significant number of the Senate Republican caucus — to take steps to protect rather than limit the special counsel demonstrates just how badly the White House has handled this issue.

Could Graham get the bill passed? Before Trump’s weird obsession with humiliating Sessions over his completely reasonable decision to recuse himself from the Russia investigation, no Republican would have proposed it. Now, though, it would only take a couple of Republicans to get it to a floor vote. Who might those votes be? Jeff Flake and Dean Heller, whom Trump threatened to fight in primaries for their re-election bids? John McCain, who has long been a Trump target? Susan Collins and Lisa Murkowski, who have been more recent targets of Trump’s ire, and who are also friends with Sessions? We might ask whether Trump can summon enough Republican support to keep the Senate from getting a veto-proof majority for Graham’s upcoming bill.

Would such a bill pass constitutional muster, however? That’s a tougher question. The Senate gets to confirm political appointees to the Department of Justice, but Mueller in this case is a direct hire, not a presidential appointment, and might be outside of Congress’ jurisdiction. Congress has another remedy in case Trump acts to dismiss Mueller — impeachment — which is what Graham implies will happen. If Congress passes the bill over Trump’s veto, though, Trump will have to sue to get it invalidated, and he’ll have to fire Mueller first to get standing to challenge it.

The point of Graham’s bill isn’t so much to get the law passed anyway. It’s to set up an unofficial vote of no confidence in Trump when it comes to his handling of this entire episode. Trump has gotten in his shots at humiliating people within the administration, and Graham’s warning that the Senate can play that game, too.