On Friday, special counsel Robert S. Mueller III finished his report on President Trump and Russia and submitted it to Attorney General William P. Barr. The Trump administration official must decide what to share with Congress and members of the public. He has said he’ll submit “principal conclusions” by the end of the weekend.

Once again, Barr is at the center of a protracted and politicized investigation that is dominating his time in office.

Barr, 68, was confirmed as attorney general in February. A Justice Department official told The Washington Post last month that Barr is viewed at the department as “a lawyer’s lawyer” and is seen as less politically minded than his predecessors, Jeff Sessions and former acting attorney general Matthew G. Whitaker.

His latest stint at the Justice Department caps a long career of public service. Barr, a Republican, worked at the CIA for four years in the 1970s. He served as a domestic policy staffer in the Reagan White House and became deputy attorney general under President George H.W. Bush in 1990, and then served as attorney general from 1991 to 1993.

Barr later held high-profile positions at the telecommunications company GTE Corp. and most recently worked as a lawyer at Kirkland & Ellis, focusing on government enforcement and regulatory actions.

Here are some key facts about Barr:

What he’s said on the role of special counsels: In a 2001 oral history, Barr explained that while serving as attorney general under Bush, he generally resisted efforts to appoint independent prosecutors to probe corruption allegations. He did so a few times to try to defuse political fights over whether the Justice Department might be making politically motivated decisions.

In his first stint as attorney general, Barr appointed three special counsels — one to investigate allegations of software piracy and a government coverup, another to examine the House bank, and a third to probe the Bush administration’s handling of a bank fraud case involving loans to Iraq.

After one such appointment, Barr noted that “a lot of people in the White House were very irritated,” but added, “I still believe it was the right thing to do.”

He has a good relationship with Mueller: Barr worked with Mueller previously in the Justice Department. The two had a “strong relationship … based on mutual respect,” Timothy Flanigan, a former Justice Department colleague of Barr’s, told The Post in February.

Flanigan said he thought Barr would be able to maintain a healthy independence from the White House and Trump, saying, “If Bill starts getting the tweet treatment, Bill is a tough guy. He’s a tough, tough guy. Not that Jeff Sessions wasn’t, but I don’t think Bill’s just going to sit there and take it. I think he would make sure that the president understood that it is not really a smart thing to be lambasting the attorney general.”

He “would have liked” for Mueller’s team to have more political diversity: Mueller’s team included some lawyers who’ve given to Democratic candidates, though Mueller is a Republican. “In my view, prosecutors who make political contributions are identifying fairly strongly with a political party,” Barr told The Post recently. “I would have liked to see [Mueller] have more balance on this group.”

He believes in broad presidential authority: Barr has long been known as a proponent of broad presidential authority and once sent a memo to Justice Department leaders that was critical of what Barr saw as Mueller’s legal theory of how the president could have obstructed justice.

Soon after his Senate confirmation, Barr wrote a memo that seemed to recognize the immense pressure he is under as attorney general at a historically contentious time for the Justice Department: “The Department has faced ever-increasing scrutiny from all quarters as news cycles have shrunk from days, to hours, to nanoseconds,” Barr wrote.

He thought Trump was right to fire James B. Comey as FBI director: In a 2017 op-ed in The Post, Barr expressed support for Trump’s decision to fire then-FBI Director James B. Comey, a decision that was criticized by Democrats and advocacy groups as possible obstruction of justice. In the op-ed, Barr criticized Comey’s handling of the Justice Department’s long-running investigation into Hillary Clinton’s emails, writing, “Comey’s basic misjudgment boxed him in, compelling him to take increasingly controversial actions giving the impression that the FBI was enmeshed in politics.”