I was appointed a United States attorney by President Ronald Reagan and later a deputy attorney general by President George H.W. Bush. All of us at the Justice Department swore an oath to defend the Constitution, not a president or political party. It is not easy for me to acknowledge that we are witnessing a slow-motion unraveling of the bedrock belief that no one is above the law, not even the president.

This unraveling is aided and abetted by a chief law enforcement officer who first articulated his extreme view of executive power more than 30 years ago: William Barr believes the attorney general is “the president’s lawyer.” He is acting like it today, breaking norms that protect the integrity of the justice system no matter who is in the White House. That is why former special counsel Robert Mueller must resist his own instincts to return to private life, and Congress must insist that the truth be told and that norms threatened today be codified into law.

We need a bipartisan response to Barr

Barr has just been thoroughly contradicted by the special counsel. Mueller’s public appearance makes all the more stunning Barr’s action in stepping in to all but exonerate the president 25 days before releasing even a redacted version of Mueller’s report which explicitly stated the opposite. This pattern of behavior by Barr is rooted in his unsolicited memo to the White House and the Justice Department auditioning for attorney general six months before he was nominated.

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In that memo, Barr laid out his extreme interpretation of presidential power and of the obstruction of justice statutes and argued it was nearly impossible for a president to commit the crime. He critically pre-judged Mueller’s conclusions before reviewing evidence, writing “Mueller’s obstruction theory is fatally misconceived.” Barr made the untenable claim that Section 1512(c)(2) does not prevent a president from exercising his or her authority over law enforcement proceedings to improperly interfere in an investigation. This extreme view literally puts a president above the law.

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How can all of us across the ideological spectrum who reject that view respond effectively?

Special counsel Robert Mueller leaves Russia investigation press conference on Wednesday, May 29, 2019.

First, Congress needs to find its voice. Article I of the Constitution gives Congress far-reaching authority to oversee the executive branch. Senate Majority Leader Mitch McConnell and Senate Judiciary Committee Chairman Lindsey Graham are actively providing political cover for Trump to eviscerate centuries-old norms. They must remind themselves that what benefits a runaway executive of their party, could empower an aspiring despot from the left next time. The Mueller report makes a very strong case that Trump obstructed justice, a conclusion more than 1,000 former prosecutors, including lifelong Republicans, reached independently.

Americans need to hear Mueller testimony

Mueller’s report includes 10 instances where President Donald Trump tried to cover up the truth, including ordering the White House Counsel Don McGahn to fire Mueller, and then ordering McGahn to “dispute the story and to create a record stating he had not been ordered to have the special counsel removed.” The president sought to influence a number of people to lie, and even directed aides to create false documents and reports. Perhaps worst of all, Trump appears to have attempted to silence a number of witnesses, by dangling pardons as a reward for stonewalling investigators. If anyone else did what the president did, they would be facing prosecution and prison. Congress must hold hearings, with or without administration witnesses.

Second, the American people need to hear direct public testimony from Robert Mueller. I have known Bob Mueller since 1977 when we were assistant U.S. attorneys in adjacent offices, and I have always respected his sense of rectitude and restraint, but he waited weeks to set the record straight. By then, the attorney general had whitewashed his report in a conclusory letter and even held a press conference to further tout the White House political spin now discredited by Mueller — discredited everywhere that is but in the minds of busy Americans without time to dissect Mueller’s 448-page, carefully-worded tome.

Given Barr’s unprecedented efforts to misstate his investigation’s findings, Mueller needs to recognize that his work is not quite done. If all he does is repeat the findings of his own report for a second time, that will in itself be a critical act of public service.

Start the climb back to the America we know

Third, Congress needs to legislate. The Mueller report identified norms smashed by this president which must be codified to have meaning again. Barr’s distressing success in obfuscating the law indicates a need for a new statute (perhaps to be called the William P. Barr No One Is Above The Law Act) reaffirming in unmistakable terms that the president is bound by the law like everyone else.

Given Barr’s assertions to the contrary, Congress should probably spell out that a president commits a crime when he or she falsifies a document or orders someone to create false official documents, uses the offer of a pardon to interfere with an ongoing law enforcement investigation, or encourages a Justice Department investigation into his or her political adversary. And this should be followed by a statement that the inclusion of these specific behaviors engaged in by Trump does not suggest the exclusion of other acts knowingly taken to obstruct an on-going investigation.

It will be a long climb back to the America we have known for generations — but unless Congress does its constitutional duty where Attorney General Barr has been derelict, future presidents might not feel compelled to lead us back in that direction at all. Patriots of all parties must stop this president from running roughshod over the Constitution we are all sworn to defend.

Donald Ayer served as a U.S. attorney and as principal deputy solicitor general in the Reagan administration and was deputy attorney general under George H.W. Bush.

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This article originally appeared on USA TODAY: Congress and Mueller need to step up and protect America from presidents like Trump