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When President Donald Trump told his Ukrainian counterpart on July 25, 2019, that he would have William Barr give him a call, Trump immortalized Barr’s role in the politically motivated pressure campaign that led to the third presidential impeachment in U.S. history. But the fateful 30-minute conversation was just one example of how Barr, more than any other Attorney General since the Watergate era, has emerged as a protector of his boss.

In his first months on the job, Barr spun in Trump’s favor investigations by special counsel Robert Mueller and Inspector General Michael Horowitz. He pushed foreign governments to help with a third probe of Trump’s perceived enemies in the FBI. Barr surged forces to American cities that Trump attacked as “Democrat-led.” He walked beside Trump through Lafayette Square in June after peaceful Black Lives Matter protesters had been violently cleared by federal agents.

At stake is the Justice Department’s reputation for independent law enforcement. It’s not clear whether Barr is guided by loyalty to Trump or a belief in sweeping Executive power. Either way, he has proved himself a top defender of the President. Trump famously criticized his previous Attorney General for what he saw as a failure to protect him. He didn’t have to worry about William Barr.

Berenson is TIME’s White House correspondent

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