Donald Ayer, Stuart Gerson and Paul Rosenzweig

Opinion contributors

When he told the president that a “real lawyer” takes notes, then-White House counsel Don McGahn showed he understood a lawyer’s proper function. He knew that a lawyer’s job is to advise clients about what the law allows and also what it prohibits. Notes are a symbol of a deeper reality — that truth and facts are at the core of the rule of law, and that lawyers are the guardians of those values.

President Donald Trump's ongoing assault on the rule of law seeks most basically to prevent lawyers from performing this role. Leading up to the release of special counsel Robert Mueller's report, we saw multiple news accounts, some based on unidentified administration officials and other sources, about a president directing law enforcement agents to ignore judicial orders; working to hollow out a vital domestic law enforcement agency, the Department of Homeland Security, because its leaders will not bend to his will; and suggesting that he will punish his political opponents by targeting them for adverse actions.

And to facilitate those and other actions, the president has taken steps to remove lawyers and other officials from their positions because they adhere to the rule of law and refuse to permit him to ignore it. A president should not fire his Homeland Security secretary for refusing to follow an illegal directive. A president cannot order the Department of Justice to investigate his political opponents for fictitious crimes, as The New York Times reports, and no president should ever contemplate ordering immigration authorities to release detainees in the home cities of his political opponents.

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We should be especially concerned by pressure on lawyers and threats to oust them. They are the ones forcing this administration to hew to statutory and constitutional limitations. The resiliency of the American experiment and the power of traditional ideals of limited government, the rule of law, and checks on executive authority are, to a very real degree, in these lawyers’ hands.

McGahn stood up to Trump, Barr did not

And now the Mueller report gives us even more evidence of the president’s disdain for legal constraints. Three times he asked McGahn to assist him in legally dubious acts. Three times McGahn refused. McGahn refused to tell Attorney General Jeff Sessions not to recuse himself from overseeing the Russia investigation; he refused to fire Mueller; and he refused to lie about the president’s requests that he fire Mueller. He stood in defense of the rule of law. The president, by contrast, said he wished his attorney was Roy Cohn — a man who was disbarred from the practice of law for his criminality and dishonesty.

Also disturbing is the recent conduct of Attorney General William Barr, our nation’s chief law enforcement officer. Mueller’s report convincingly demonstrates systematic actions by the president to obstruct an ongoing criminal investigation, irrespective of whether a sitting president can be indicted. Despite this, the attorney general, acting more like a presidential defense attorney than a representative of the American public, ignored the impact of Mueller's negative findings and stated refusal to exculpate the president from a charge of obstruction.

Lawyers are a bulwark against chaos

These and other recent steps to secure a narrow political advantage by impairing our legal institutions and undermining faith in them are a gross offense to the idea that no man or woman is above the law. In the end, all of our liberties, and our democratic system of government, depend upon maintaining the rule of law by reliance on the independent judiciary, the separation of powers and limited government.

Shakespeare knew the dangers of what President Trump is doing. In "Henry VI," Dick the butcher and Jack Cade are plotting a traitorous revolution against society and they recognize that the first thing they need to do to create chaos, eliminate liberty, and advance autocracy is to destroy what binds a society together — that is, to end the rule of law that is a bulwark against authoritarian rule. And so they say, “The first thing we do, let’s kill all the lawyers.”

Donald Ayer was deputy attorney general in the George H.W. Bush administration. Stuart Gerson was an assistant attorney general in the H.W. Bush administration. Paul Rosenzweig was senior counsel to Kenneth Starr in the Whitewater investigation and a deputy assistant secretary of Homeland Security in the George W. Bush administration. Follow them on Twitter: @stuartmgerson and @RosenzweigP