Congress is letting Trump decide what it can investigate. This is bigger than Lewandowski.

It’s official. Corey Lewandowski is contemptuous of Congress. He’s also in contempt of Congress. That’s serious enough and it can — and should — land Lewandowski in jail. But, in the long run, his repeated refusal to answer questions put to him by the House Judiciary Committee on Tuesday may well be less serious than allowing a witness to openly mock a congressional investigation.

Though he appeared in response to a subpoena and testified under oath, Lewandowski might as well have been on CNN making snide remarks to Ana Navarro. To give you the flavor of his testimony, he taunted California Rep. Eric Swalwell for his failed presidential campaign, characterized one of Texas Rep. Sheila Jackson Lee's questions as “just a rant,” repeatedly forced House members to read to him from the Mueller report and demanded that the committee “afford me the same privilege you afforded" special counsel Robert Mueller.

“It’s a big safe, congressman. There’s a lot of guns in there,” he told Swalwell at one point. And when caught in a lie, he responded, “Oh, I’m sorry. Nobody in front of Congress has ever lied to the public before. I’m sorry.”

Trump aims to cut off all scrutiny

Rudeness and flippancy aren’t typically legally actionable, but refusing to answer congressional questions is. And Lewandowski refused to answer even the most basic questions too many times to count. He even refused to answer questions about the Stormy Daniels payoff.

Ostensibly, he did so based on a letter sent by the White House that claimed “executive privilege” and instructed Lewandowski not to reveal information about conversations with the president or his senior advisers that went beyond what was in the Mueller report.

President Donald Trump has made some expansive claims of executive privilege in the past, but claiming there is a privilege for conversations with Lewandowski is something special. It's one thing to claim privilege for Cabinet members and White House staff. Extending it to people like Lewandowski would effectively make the president immune from any sort of congressional investigation at all.

Trump fired Lewandowski as his campaign manager in June 2016, and Lewandowski never advised or worked for Trump as president. He is nothing more than a guy who happens to know Trump, just like someone who’s a member of the Mar-a-Lago Club. If Trump can prevent Lewandowski from testifying about their interactions, he can prevent testimony from anyone. That is neither wise nor constitutional.

Congress is giving away its powers

The committee prefers to keep the focus on Trump rather than hold Lewandowski in contempt, according to a Washington Post report citing unidentified Democratic officials. But this isn’t just about Trump anymore. It’s about whether Congress is going to live up to its alleged role as a co-equal branch of government, or devolve into a vestigial debating society like the United Kingdom's House of Lords.

A great deal of the trouble caused by Trump over the past three years is of Congress’ own making. Over several decades, it has ceded more and more power to the executive branch. While Trump has consistently pushed the boundaries and bent the rules, the boundaries are where they are because Congress put them there. If Congress hadn’t abdicated control over tariffs, there would be no trade war. If Congress hadn’t allowed presidents to unilaterally declare effectively unreviewable emergencies, Trump would not be trying to short-circuit the Constitution and build his border wall without congressional authorization.

Now Congress is making the same mistake with its investigatory powers as it did with its legislative powers. Sooner or later, Trump will be just a memory. But if Congress allows the executive branch to pick and choose what it can investigate and dictate what testimony it can hear, our great-grandchildren will still be suffering the consequences.

How to hold Lewandowski accountable? Congress has to rely on the Justice Department to bring an action for criminal contempt, so that’s out. It could bring its own action for civil enforcement but that would take months, even years, to resolve.

Use contempt power to jail Lewandowski

But there’s a third way. Congress has an inherent contempt power that allows it to jail anyone who refuses to provide testimony. This power hasn’t been used since 1935 and locking up, say, a Cabinet member who refused to answer questions could spark a constitutional crisis. But Lewandowski isn’t a Cabinet member. He’s just some guy who has decided he doesn't want to testify about some things.

The advantage of using these inherent contempt powers, apart from demonstrating that Congress takes its investigative powers seriously and will fight to defend them, is that it would bring Trump’s absurd “executive privilege” claim to a quick resolution. The House would vote to hold Lewandowski in contempt and then order him back and give him another chance to answer the questions. If he refused, he’d be jailed. Lewandowski, backed by the Trump administration, would immediately bring a court action challenging the contempt finding which, since he would be incarcerated, would be heard quickly.

There’s more at stake here than investigating whether and how Trump tried to frustrate the Mueller investigation. Lewandowski’s performance Tuesday can’t be allowed to go unchallenged. One way or another, his testimony will set a precedent for what happens to those who openly defy Congress, or for what doesn’t.

Chris Truax, an appellate lawyer in San Diego, is an adviser to Republicans for the Rule of Law and a member of USA TODAY's Board of Contributors.

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This article originally appeared on USA TODAY: Trump investigations will go nowhere unless Congress asserts powers