Following Attorney General William Barr's Wednesday appearance before the Senate Judiciary Committee, one thing is now very clear: Barr holds Congress in contempt. Congress should reciprocate.

Barr's scorn for legislative oversight was apparent throughout the day as he evaded, prevaricated, and generally dodged questions posed by Senate Democrats. The most stunning moment came when the Ivy League-educated lawyer, confronted by Sen. Kamala Harris (D-Calif.), suddenly and improbably seemed to lose his grasp on the English language.

"Has the president or anyone at the White House ever asked or suggested you open an investigation into anyone?" she asked.

Barr stumbled. "I'm trying to grapple with the word 'suggest,'" Barr said. It looked for all the world like a clear effort to sidestep a simple question. And it was a moment that, if there's any justice, will go down in American political history alongside "It depends on what the meaning of 'is' is."

Here is the complete exchange, via CSPAN, between Kamala Harris and Bill Barr — including the part where Barr couldn't say whether Trump or anyone in the White House has ever suggested that he open an investigation into anyone. It's worth a watch. pic.twitter.com/wJOdSFR7JR — Kyle Griffin (@kylegriffin1) May 1, 2019

That exchange was certainly memorable. But the real moment of truth should arrive today — if, as expected, Barr refuses to show up for a scheduled hearing before the House Judiciary Committee. This comes as the Department of Justice also refuses to hand over Special Counsel Robert Mueller's unredacted investigative report to the committee — a double act of defiance.

Barr's reason for skipping? He says he shouldn't have to answer questions from lawyers on the committee's staff — that he should only have to take queries from the elected members of the committee itself. "The attorney general remains happy to engage directly with members on their questions regarding the report and looks forward to continue working with the committee on their oversight requests," Barr's spokeswoman said Wednesday.

That almost sounds reasonable, except for one thing: Oversight isn't something that Congress requests. Congress is a co-equal branch of government, not a sidekick to the president. The House Judiciary Committee has the power to subpoena witnesses, to recommend prosecution for perjury if those witnesses lie, and to hold them in contempt if they don't show up at all. Congress has the power to seek the truth about our nation's governance, and it doesn't have to be nice about it. "When push comes to shove, the administration cannot dictate the terms of our hearing in our hearing room," Rep. Jerrold Nadler (D-N.Y.), chairman of the committee, said Wednesday.

He's right. And there's a simple solution for the House to enact if Barr really doesn't show up: Formally hold him in contempt of Congress, then send him to jail.

That's a radical suggestion, but this is a radical moment.

Barr's defiance of the committee isn't happening in a vacuum: It's part of a sweeping effort by President Trump's administration to defy nearly all oversight by Congress. In recent weeks, the White House has refused to make witnesses available to committees, balked at handing over documents, and even gone to court to keep information about the president from being released. The executive and legislative branches have often butted heads on oversight issues, but Trump's strategy amounts to a wholesale rejection of Congressional prerogatives. "We're fighting all the subpoenas," the president told reporters last week.

This is where House Speaker Nancy Pelosi (D-Calif.) comes in.

Pelosi comes under fire regularly from progressives because of her reluctance to pursue impeachment of the president. She appears to prefer an approach of conducting as many investigations of Trump and his administration as possible — seemingly in hopes that a steady drip of ugly information about the president will convince voters to do the right thing and turn him out of office in 2020.

But that approach won't work if Trump can shrug off Congress without consequence — or slow-walk oversight efforts until after the election.

Pelosi, though, is never stronger than when defending the rights of the House of Representatives. Remember: She brought Trump to heel earlier this year, refusing him a venue for the State of the Union speech until he brought an end to the government shutdown over his request for border wall funding. It was the best moment thus far of Pelosi's second stint as speaker.

If Barr continues to refuse to testify, Pelosi will be faced with two choices: She can let it go, and accept that Trump will be impervious to any kind of accountability for the remainder of his presidency. Or the House she leads can impose consequences.

Sending Barr to jail for contempt would be a big consequence.

That's very much on the list of possibilities, if House Democrats have courage. "If good faith negotiations don't result in a pledge of compliance in the next day or two, the next step is seeking a contempt citation against the attorney general," Nadler said this week.

Short of imprisonment, there are other steps the House can take — including fining Barr if he continues to avoid the committee — but this is Trump we're talking about: There's no point in using incremental half-measures to get him and his administration to do the right, lawful thing. Congress is running out of options. It's time to make a radical, unmistakable stand. If not, legislators will deserve the contempt Barr has so clearly aimed at them.