In a rare wave of accountability for police brutality in the United States in recent weeks, four police officers were arrested in Minneapolis, a police chief was fired in Louisville, and officers were charged with felony assault in Atlanta, Buffalo and New York City.

Now the top law enforcement official in the country, the attorney general, William Barr, is facing an internal crisis of confidence and growing calls for his own resignation.

Barr stands accused of directing violence against peaceful demonstrators outside the White House earlier this month, and with peddling a conspiracy theory advanced by Donald Trump in an attempt to smear protesters, who enjoy wide public support.

In the first 16 months of his tenure, Barr caught criticism for compromising justice department independence with his seemingly lockstep defense of Trump, whether he was protecting the president from the investigation of special counsel Robert Mueller or intervening in criminal cases against the former Trump aides Michael Flynn and Roger Stone.

But Barr’s critics now fear that he has taken a new step, of trying on a military hat as the president’s top lieutenant in the antagonistic posture the White House has taken against street protests that have sprung up after the killing of George Floyd, an African American man, in Minneapolis by white police officers.

Nearly 1,600 former justice department officials published an open letter to the department’s inspector general on Wednesday demanding an internal investigation of Barr’s actions in response to street protests.

The attorney general’s denial at the weekend that systemic racism was a problem in US law enforcement prompted new calls for his resignation.

“I think there’s racism in the United States still, but I don’t think that the law enforcement system is systemically racist,” Barr told CBS News’ Face the Nation. “And I would say, you know, the president, before any of this happened, was out in front on this issue.”

On no planet has Trump been “out in front” in the campaign against racist policing, said Kandace Montgomery, director of Black Visions, a Twin Cities-based activist organization.

“William Barr is a white man who is serving a racist administration, so of course he’s going to deny the fact that the current law enforcement system is systemically racist,” Montgomery said. “History and facts have proven otherwise. But we know how that administration feels about facts.”

While Barr does not credit the reality of systemic racism, he is an eager proponent of an elaborate conspiracy theory about the protests advanced by Trump, who tweeted this week that an elderly activist pushed to the ground by police in Buffalo, New York, “could be an antifa provocateur”.

None of 51 individuals facing federal charges in connection with protests in recent weeks has any alleged link to any such conspiracy, according to court documents reviewed by NPR.

Challenged on the hole in the “antifa” story, Barr told told Fox News on Monday that the relevant cases were still in process. “We have some investigations under way, very focused investigations on certain individuals that relate to antifa,” he said.

On account of a deference to Trump that has been perceived as excessive, Barr has in the past been embroiled in criticism, for dropping the prosecution of Trump cronies; distorting the findings of Mueller; advancing investigations seemingly designed to harm Trump opponent Joe Biden; defending Trump’s firing of inspectors general and more.

“He can’t function in the job as the founders intended the job to be done, and he needs to be removed,” said Donald K Sherman, deputy director of the Citizens for Responsibility and Ethics in Washington watchdog group. “We have seen him literally bend the scales of justice to protect the president’s rich, white, criminal allies, versus what he has done to people who have dared to stand up peacefully against racial injustice in America.”

With the rise of a national protest movement for racial equality, a new Barr has emerged, his critics say – one who seems ready to lead Trump’s charge against American citizens on US soil.

Barr has disputed reports that he personally ordered a violent crackdown outside the White House on 1 June to clear protesters for a Trump photo op at a church, telling the Associated Press: “My attitude was: get it done. But I didn’t say, ‘Go do it’.”

But Barr was spotted reviewing security arrangements outside the White House shortly before the crackdown began, and Trump’s press secretary said flatly on Monday: “It was AG Barr who made the decision.”

Neil Kinkopf, a Georgia State law professor who worked in the Office of Legal Counsel under Bill Clinton, said it was “quite unusual” for an attorney general to personally direct security forces.

“It isn’t unusual for the attorney general to give the president legal advice about what his authorities are in responding to crises, including responding to unrest of the sort that we’re seeing,” said Kinkopf, noting that President Dwight Eisenhower’s attorney general issued a legal opinion in 1957 before troops were sent to enforce school desegregation in Arkansas. 

“What’s unusual about what Barr appears to have done is taking a role in directing the use of force, ordering the use of force – that’s a military function, not a justice department function.”

As attorney general, Barr could bring immense pressure to bear in achieving police reform. In 14 cases under Barack Obama, the justice department cracked down on police departments with sanctions known as consent decrees and ended the distribution of military-style combat gear to police departments.

But Trump, who has personally encouraged police brutality, threw out an Obama-era blueprint for police reform, reversed the decision on military gear and has stopped the use of consent decrees.

“Just because we don’t use that particular tool in every instance doesn’t mean that we’re not doing something about it,’ Barr told CBS.

Military force against protesters

Barr has tried to downplay Trump’s open enthusiasm for deploying military force in American cities, denying reports that the president wanted to respond to demonstrators outside the White House by invoking the Insurrection Act and mobilizing 10,000 troops.

“The president never asked or suggested that we needed to deploy regular troops” to clear the area around the White House, Barr claimed.

In the hours before protesters outside the White House were gassed, however, Trump held a call with state governors in which the president demanded more aggressive use of force against the demonstrators.

“You have to dominate or you’ll look like a bunch of jerks. You have to arrest and try people,” Trump said on the call.

Barr himself then spoke on the call, advising the governors that the federal government would rely on the Joint Terrorism Task Force – a national law enforcement network that was beefed up after the September 11 attacks – to coordinate operations.

“It’s a tried and true system, it’s worked for domestic homegrown terrorists, and we’re going to apply that model,” Barr said on the call.

Trump then tweeted an enthusiastic endorsement of the Republican senator Tom Cotton’s call for the deployment of the 101st Airborne, an elite US army combat unit typically deployed in some of the world’s most rugged corners, against US citizens. “100% Correct,” Trump wrote. “Thank you Tom!”

Donald Sherman said that Barr’s masquerade as a military man amounted to “an abuse of power, and it is a harbinger of potentially worse things to come.”

“Donald Trump contested and refused to believe the results of an election that he won,” Sherman said. “So I think it is reasonable to be concerned about what the attorney general’s role is in enabling his conspiracy theories and his attacks on democratic institutions.

“The stakes are only going to get higher from here.”