Despair about Congress is as old as the nation itself. In 1789, less than three months into the First Congress, Rep. Fisher Ames of Massachusetts wrote that he “felt chagrined at the yawning listlessness” of his chamber. Five years later, Vice President John Adams, presiding officer of the Senate, wrote to his wife, Abigail, that “(t) he Business of Congress this session is Dulness Flatness and Insipidity itself.”

In the intervening two and a quarter centuries, Congress’ public standing has gone up and down, but disparaging the national legislature has remained quintessentially American. Political scientists John Hibbing and Elizabeth Theiss-Morse have argued that this is because Americans want “stealth democracy”: We say we value robust debate, disagreement and compromise, but then recoil when we actually see those qualities in action.

But that doesn’t make it any less important to have a national institution that instantiates those qualities — especially when a great many Americans deeply distrust the president.

So, at a time like this, what might we expect Congress to do? And, perhaps more important, why might we expect it to do anything, given that both houses are controlled by President Trump’s party?

The answer to the first question cannot be that we expect it to pass legislation. Given the presidential veto power, legislation aimed primarily at checking the president tends to be passed only when presidents’ hands are forced — for example, in the aftermath of major presidential scandals like Watergate. But thinking just in terms of passing legislation is thinking too narrowly. Congress does a lot more than pass laws.

The list of tools that Congress can use to check the executive is long, including things like refusing to fund programs it doesn’t like, refusing to confirm nominees, and impeaching. Importantly, each of these can be used to effect change in collateral policy areas: Congress can hold up funding or confirmations to bring the administration to the bargaining table on some other issue. Indeed, throughout American history, Congress has done so repeatedly.

In recent months, the most prominent of Congress’ executive-checking tools has been the power of each chamber to conduct investigations, complete with public hearings, subpoenas, and the threat of a contempt citation if those subpoenas are defied. Although the majority party runs the show in hearings, members of the minority have plenty of opportunity to ask questions and make the points they wish to convey, both to the witnesses and to the American people.

At the moment, four congressional committees are investigating links between Russia and the Trump campaign and administration. These hearings all attracted significant public attention, and none of them redounded to the administration’s credit.

Importantly, the hearings serve both an inward-facing and an outward-facing purpose. Internally, they serve to move along the committees’ own inquiries into what happened. These inquiries are likely to take a good bit of time, and could result in anything from proposed legislation to impeachment proceedings to requiring heightened assurances before confirming future nominees. Or they could result in no action at all.

Perhaps more important is their public-facing function. Members of Congress and their staffs use open hearings — especially high-profile ones — to make a case directly to the public and to argue for support. Opponents of the administration have used the hearings to try to convince the public that the administration has obstructed justice and may have colluded with the Russian government’s attempts to influence the election. Supporters of the administration have pushed back.

If Trump’s approval ratings and the results of special elections in recent months are any indication, the message of administration opponents seems to resonate more. And, of course, the lower Trump’s approval sinks, the more emboldened his opponents will be; at the same time, the costs of supporting him will grow.

It takes a lot for members of a president’s own party to turn on him, but sustained low poll numbers — especially when they drag down the re-election prospects of members of Congress — can do it. Just consider how much trouble George W. Bush had moving his legislative agenda (like Social Security reform) and nominees (like Harriet Miers for the Supreme Court) through the GOP-dominated Congress as his approval numbers tanked in his second term.

None of this is inevitable, of course. Trump’s poll numbers could rebound, in which case one would expect to see Republicans fall in line behind him. But the longer Trump suffers in the public sphere, the more likely Congress is to cast off its yawning listlessness.

Josh Chafetz is a professor of law at Cornell Law School and the author of “Congress’s Constitution: Legislative Authority and the Separation of Powers.” He wrote this for the Philadelphia Inquirer.