It now seems only a matter of time before Republicans move to impeach Joe Biden. On what grounds, exactly? They’re still working that out. But House Speaker Kevin McCarthy, who has gone back and forth with his conference on the impeachment question, all but endorsed such a move Sunday—and even attempted to use the promise of an impeachment inquiry to get some of his most extreme members to back off their threats to shut down the government. “If you look at all the information we have been able to gather so far,” McCarthy told Fox News on Sunday, “it is a natural step forward that you would have to go to an impeachment inquiry.”

Such an inquiry, he said, “provides Congress the apex of legal power to get all the information they need.”

Thus far, Republican investigators have failed to produce evidence of wrongdoing by the president—and not for lack of trying. Not only have they investigated him over everything from his son Hunter Biden’s business dealings to his border policies to his supposed “weaponization of the federal government”—they have at times fought one another over who would get to lead the impeachment charge. But they haven’t established any misconduct by Biden himself, instead offering up insinuation about his supposed impropriety on cable news.

Some far-right lawmakers have been clamoring for a Biden impeachment since the GOP assumed its narrow House majority earlier this year—to the chagrin, at times, of McCarthy, who worked earlier this summer to tamp down a push from Lauren Boebert. But the House speaker has expressed more support for the idea in recent months; in July, he told Sean Hannity that the House probe into the Biden family was “rising to the level of impeachment inquiry,” though he stopped short of formally calling for one. On Sunday, he came closer still to endorsing the move—suggesting it was a matter of when, not if, his conference would seek the president’s ouster.

McCarthy, like others in his conference, seems to be looking to provide political cover for Donald Trump, who surrendered last week in Georgia in his fourth felony indictment this year. With every Trump indictment Republicans have sought to recenter attention back to the Biden family. McCarthy is said to have committed to expunging Trump's two impeachments. (Trump, of course, maintains he's done nothing wrong). But the House speaker also appears to be using the promise of an impeachment inquiry for his own political ends. Knowing that the Senate is led by Democratic Leader Chuck Schumer, McCarthy is hoping to pass a stopgap spending bill to buy more time for a government funding agreement. But the House Freedom Caucus, which can threaten his speakership at any time, is staging yet another rebellion, vowing to block the proposed spending measure unless their outrageous, somewhat amorphous demands are met—raising the prospect of a government shutdown. “We’ve got to hold the line,” Republican Congressman Chip Roy said last week. But McCarthy, seeking some leverage over his far-right members, pointedly noted Sunday that a shutdown of the government would also mean a shutdown in their Biden probe: “If we shut down, all the government shuts it down—investigation and everything else,” the speaker said. “It hurts the American public.”

An impeachment, of course, will not bring about Biden’s ouster; even if the push succeeds in the House, it’s certain to be a non-starter in the Democratically-controlled Senate. But he clearly sees it as a means to advance his party leader’s interests, and especially his own. The question is how long he can publicly flirt with such a measure before his party demands action.