Throughout the impeachment process, House Democrats have emphasized that all presidents before Donald Trump complied with congressional subpoenas. Under all other administrations, they say, witnesses came when Congress summoned, and documents Congress requested were produced. But today everything has changed. Congress is supposedly powerless to obtain what Trump has consistently denied them.

Perpetuating this narrative, House Intelligence Committee Chairman Adam Schiff said on Fox News Sunday, “I would just say to my Republican colleagues…if they’re prepared to say a president can simply say no to any congressional subpoena and tie up Congress for years in litigation…are we really prepared to go down that road?”

But is Congress as neutered as House Democrats imply? Can presidents effectively ignore the legislative branch by tying it up in “years” of litigation, as Schiff complained on Sunday?

A vote of the full House on impeachment is expected on Wednesday, and then it’s on to the Senate. There are mixed signals as to whether Senate Majority Leader Mitch McConnell will give impeachment the full airing of grievances it would receive in a trial, but if he does, it will be interesting to see whether witnesses continue to flout subpoenas.

With that in mind, let’s examine the history and court precedent, as well as what’s likely to happen in the Senate.

There was a lot left uncovered during the House process due to the rush to hold the impeachment vote before Christmas. Originally, Democrats had subpoenaed State Department chief Mike Pompeo and documents relating to the pause on lethal aid to Ukraine. State, however, refused to cooperate because the House had not held a vote to launch an impeachment inquiry. After the House held the vote, Democrats did not reissue the State Department subpoenas.

Former national security adviser John Bolton, who has first-hand knowledge of the details surrounding the held-up Ukraine aid, was originally subpoenaed by House Democrats as well. But after Bolton’s attorney requested clarification from the courts as to whether the legislative branch inquiry or the asserted privilege of the executive branch takes precedence, the House decided to forego its subpoena of Bolton.

“I think it was interesting that the House didn’t subpoena Bolton, because it suggests…that they don’t care about getting his evidence even though they claim it would be very incriminating,” attorney Sam Dewey told TAC. Dewey, who has worked on key committees in both Houses of Congress, suggested those issues could be raised again in the event of a Senate trial.

But will Democrats in the Senate reissue these subpoenas? What happens if the executive branch refuses to cooperate? Will Joe and Hunter Biden appear if they are summoned by Republicans? What can Congress can do if witnesses don’t show?

Congress has three options if witnesses ignore subpoenas or do not produce documents, constitutional experts told TAC, all of which involve contempt citations. Congress can refer them to the U.S. attorney to consider criminal prosecution, file suit and ask the courts to enforce it, or use inherent contempt.

Due process requires that the person alleged to be in contempt be given notice and an opportunity to respond with evidence and a defense, which means a trial. Congress has its choice here: it can pursue a criminal trial, a civil trial, or a trial on the floor of the congressional chamber itself. That last option hasn’t been exercised since 1935, when Congress arrested and tried William P. MacCracken Jr., a former assistant commerce secretary, for contempt after he destroyed Air Mail scandal files that had been subpoenaed.

In the 1920s, as Congress investigated Warren Harding’s scandals and the Teapot Dome affair unfolded, members suspected Attorney General Harry Daugherty was personally corrupt and shielding others in the administration. When a Senate committee subpoenaed Mally Daugherty, the attorney general’s brother, he refused to testify or surrender the requested documents. The Senate then dispatched the sergeant at arms of the Senate to place him under arrest in Cincinnati, and held him in custody.

A federal district court freed Daugherty on a writ of habeas corpus, but the Supreme Court reversed that decision in the 1927 case McGrain v. Daugherty. The Court ruled that the Senate has the power to directly arrest and bring witnesses against their will to Washington to testify.

In ruling that Congress can compel compliance with subpoenas through direct arrest and detention, the Court wrote: “Experience has taught that mere requests for such information often are unavailing, and also that information which is volunteered is not always accurate or complete; so some means of compulsion are essential to obtain that which is needed.”

But over the years, the legislative branch has become loathe to use its power to directly arrest.

When Congress voted to hold Obama’s attorney general Eric Holder in contempt for his role in the “Fast and Furious” gun running scandal, House Speaker John Boehner recommended the matter for criminal prosecution—which means he asked Holder to investigate himself. Boehner didn’t attempt to file a civil enforcement suit, the way House Democrats are doing with Trump’s taxes, or hold an inherent contempt trial on the House floor. (Keep that in mind every time you see congressmen peacock in front of the cameras about how the executive branch ignores them.)

When Congress chooses to make overtures rather than use its vast enforcement tools, it fundamentally undermines its own powers, argues constitutional attorney Bruce Fein.

“The idea that Congress has to wait for the courts as asserted by House Democrats is delusional,” Fein told TAC. The Constitution, he says, gives the House and Senate inherent power to hold hearings and launch oversight investigations, in addition to any civil or criminal court recourses they might choose to pursue.

The Supreme Court has already held that the House does not have to wait for the courts, says Fein. Furthermore, an impeachment trial is not a criminal trial; it is political. And Hamilton wrote in Federalist 65 that Congress need not meet any criminal standards. Therefore, House Democrats don’t need prosecutors to argue their case.

“The real thing at issue here is the violation of the president’s oath of office,” Fein said. “If they impeach Trump, he’ll simply become an elder statesman and make thousands of dollars a speech like Richard Nixon or Bill Clinton or other former presidents. No one is going to jail at the end of this trial.”

In announcing the House impeachment articles against President Donald Trump, House Speaker Nancy Pelosi said, “Our president holds the ultimate public trust. When he betrays that trust and puts himself before country, he endangers the Constitution, he endangers our democracy, and he endangers our national security. The Framers of the Constitution prescribed a clear remedy for presidents who so violate their oath of office. That is the power of impeachment.”

But back in 2007, when Fein was working on impeaching President George W. Bush and Vice President Dick Cheney, Pelosi said that impeachment was off the table completely.

So “long as they think their party has a chance to get the White House back…they’re eager to take Trump’s usurpations and imitate them with executive orders of their own,” Fein said.

Ultimately, according to Fein, both parties in Congress “have no concept of the separation of powers. It’s all about loyalty to party. None of the Democrats did anything about Obama going to war illegally, the Snowden revelations, DACA. Democrats didn’t complain at all about that. Republicans are exactly the same. …There’s no longer any loyalty to the oath of office. That’s why the country’s institutions are collapsing.”

Nancy Pelosi is worried that impeachment will cost the Democrats their 2016 purple gains, and with it, her speaker’s gavel.

Yet in the end, her political calculation may prove shortsighted. After all, her limp and rushed use of the House impeachment inquiry has unified Trump supporters, calcified executive overreach, and played directly into Trump’s hands.