On Monday, the Republican majority of the House Intelligence Committee voted to release a memo produced by committee Chairman Devin Nunes, reportedly professing to show evidence that the FBI and the DOJ are infested with partisan enemies of President Trump. Apparently, according to this Nunes memo, these rogue deep state agents have invented the Russia investigation out of whole cloth to discredit the president.

Nunes, of course, is guilty of doing precisely what he is purporting to attack. The DOJ has called it “extraordinarily reckless” to release the memo without even checking it for national security implications. Trump’s own FBI Director Christopher Wray, meanwhile, has reportedly opposed the release of the memo on the grounds that it pushes a false narrative based on inaccurate information, Bloomberg News reported on Wednesday. This news was soon followed by a statement from the FBI denouncing the memo as misleading and inaccurate. But Republicans have rushed ahead and for an obvious reason: to discredit the FBI and the DOJ, laying the political groundwork for whatever the next phase might be in the president’s war on special counsel Robert Mueller and Deputy Attorney General Rod Rosenstein, to whom Mueller reports. Unsurprisingly, then, committee Republicans refused to release Democratic members’ dissenting memo.

This isn’t oversight: Republicans don’t even know what Mueller has uncovered. They simply want to protect Trump: If that means undermining nonpartisan law enforcement, so be it. (Strictly speaking, the committee’s vote allows Trump to release the memo, because as president he can declassify it. No prizes for guessing what he wants to do.) House Speaker Paul Ryan is fully on board, stating on Tuesday that he favors “cleans[ing]” the FBI even though he has no idea what is to be cleansed.

How can Democrats respond? There is one path of maximal resistance that would likely be highly contentious but also highly effective: Use the Constitution to play tit for tat.

The Speech or Debate Clause of the Constitution (Article I, Section 6, Clause 1) provides that “for any Speech or Debate in either House, [members of Congress] shall not be questioned in any other Place.” An unbroken two-centuries-old tradition has rightfully interpreted this provision as forbidding prosecution or lawsuits against a legislator for speeches made on the floor or in committee.

Democrats must make clear that if the memo is released, they will take to the floor or the committee and release their own memos into the record, relying on and quoting confidential information if need be. If such information reveals that President Trump obstructed justice, or that the Trump Organization is propped up by laundered Russian money, or White House aides lied to law enforcement, or Jared Kushner agreed to lift Russian sanctions in exchange for Russian election assistance, or anything else, then so be it. The threat to reveal a truth far more damaging than Nunes’ cooked-up memo might get Trump and the Republicans to reconsider their game of high-stakes chicken with the rule of law. And Democrats will be immune from any legal retribution.

This immunity is pretty close to absolute: The Supreme Court held in 1973 that the clause shields members of Congress from prosecution for anything that involves a legislative activity. In an essay written for the Heritage Foundation, Circuit Judge James Buckley—older brother of William—argued that it would even include stolen classified information. He’s right: in 1971, Sen. Mike Gravel of Alaska read the Pentagon Papers into the record of a subcommittee he chaired, at a hearing he called for specifically this purpose. The Supreme Court called Gravel’s claim of immunity “incontrovertible.”

If such strong immunity exists, why haven’t members of Congress read classified information into the record more often? Most likely it’s because they think it’s a terrible idea. It’s a long-held norm—and basic patriotism—that you don’t use classified information for partisan political advantage. But as Republicans have shown, nowadays, norms are for suckers: They have no compunction breaking them. That requires a stiff and brutal counterattack. Such reprisal would not be for political advantage but rather to reinforce the conclusion of the U.S. intelligence community, namely, that Russia interfered in American elections and continues to do so with the acquiescence and potential active support of the Trump administration.

The Speech or Debate Clause does not cover everything that a member of Congress might do. The court held in 1979 that the “Golden Fleece” award given by Sen. William Proxmire for what he considered wasteful federal spending didn’t count: It was a press release, the justices held, not legislative activity. But that’s the beauty of the Democratic threat: It is a direct response to an action by the House Intelligence Committee majority. It is thus about as core of a legislative function as one can imagine.

During Barack Obama’s presidency, Republicans loved to castigate the president and his Democratic defenders as “Chicago politicians.” During the Benghazi Committee investigation, Chairman Trey Gowdy’s continual misleading leaks were decried by Democrats but they never used the Speech or Debate Clause to answer. They should have, and they must do so now. In the 1987 movie The Untouchables, Sean Connery’s veteran cop Jimmy Malone tells Kevin Costner’s Eliot Ness, “[if] he sends one of yours to the hospital, you send one of his to the morgue. That’s the Chicago way.” Under Trump, Republicans are treating national governance as roughly equivalent to Al Capone’s Chicago. It’s time for Democrats to match them with their own brutal—but constitutionally protected—tactics. It’s apparently now the D.C. way.