WASHINGTON — William Barr knew that he was stepping into a firestorm when he accepted President Donald Trump’s nomination late last year to replace the attorney general Trump angrily pushed aside.

As special counsel Robert Mueller’s sprawling investigation wound down, it would be up to Trump's new attorney general to manage the politically fraught job of deciding which of its conclusions could be revealed to the public – when and how. He did it both quickly and in a way that has thrust him squarely into a harsh public spotlight.

He first revealed a summary of Mueller's conclusions last month that included quotations favorable to the president while omitting more damaging material that had been part of the same passages. Just before the report's release Thursday, he echoed a favorite Trump talking point – "no collusion" – in affirming that the president would face no criminal charges as a result of an all-consuming 22-month investigation, though the special counsel pointedly did not use that word.

Now, the attorney general who entered office walking a political tightrope between a mercurial White House and congressional Democrats skeptical of his intentions has raised fresh questions about the independence of the Justice Department.

In Barr, Democrats increasingly believe, that Trump has found an attorney general who will protect him after bitterly complaining that former Attorney General Jeff Sessions had abandoned him by recusing himself from the Russia probe.

Just hours after Barr released the 448-page document, which did not recommend criminal charges against the president yet chronicled Trump's repeated efforts to stifle Mueller's inquiry and a series of steps by his aides to benefit from Russian efforts to help him win the presidency, Democrats threw down a marker highlighting their distrust, issuing a subpoena demanding that the attorney general release a complete version of the report.

“My committee needs and is entitled to the full version of the report and the underlying evidence consistent with past practice," House Judiciary Chairman Jerry Nadler, D-N.Y., said Friday.

Justice spokeswoman Kerri Kupec Friday called the subpoena "premature and unnecessary," adding that the report released Thursday contained "only minimal redactions."

Still, Nadler's action served to underscore a deepening suspicion Democrats have expressed for Barr, who some lawmakers once saw as a stabilizing force for a department that Trump publicly castigated for its support of the Russia investigation. They focused in particular on a press conference Thursday in which he stressed that Trump had not committed a crime and argued the president had acted out of anger and frustration.

He delivered that absolution hours before releasing a report describing conduct that Barr had told lawmakers he would not tolerate as attorney general. During his confirmation hearing in January, Barr vowed that he would "resign rather than follow an order to terminate the special counsel without good cause."

One episode detailed in Mueller's report showed that Trump had asked his aides to do just that, one of a series of actions Mueller's office examined in which the president sought to intercede in the investigation that loomed over his presidency. In many cases, according to the report, White House Counsel Don McGahn, Attorney General Jeff Sessions and adviser Corey Lewandowski,ignored his orders, possibly saving the president from criminal obstruction charges.

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Democrats had been skeptical of Barr's handling of the report since March, when he announced its central findings. But lawmakers said their suspicions hardened when they saw the details the attorney general had kept secret for nearly a month.

In a bare-bones March 24 summary of Mueller's major conclusions, the attorney general revealed that he and Deputy Attorney General Rod Rosenstein made the final determination that Trump's conduct did not constitute a crime of obstruction. Barr said he acted because Mueller's inquiry did not reach a conclusion.

Within that summary, Barr also offered only partial passages from Mueller's report that appeared to present the conclusions in a way that favored the president, including the central finding that "the investigation did not establish that members of the Trump campaign conspired or coordinated with the Russian government in its election interference campaign."

The more complete conclusion, however, was contained in Mueller's fuller report Thursday: "Although the investigation established that the Russian government perceived it would benefit from a Trump presidency and worked to secure that outcome, and that the campaign expected it would benefit electorally from information stolen and released through Russian efforts, the investigation did not establish that members of the Trump campaign conspired or coordinated with the Russian government in its election interference activities."

Barr raised more eyebrows last week when he told a Senate panel that Justice is reviewing whether federal authorities improperly spied on Trump's campaign during the early stages of Russia investigation.

"I think spying did occur," Barr told lawmakers. "The question is whether it was adequately predicated."

The remarks were immediately embraced by Trump and some Republican lawmakers who have long pushed for such a review because of their suspicions that the FBI and the Justice Department had actively worked against the president's campaign.

"There is a hunger for this to happen," Trump said after learning of the attorney general's testimony.

Democrats said Barr's choice of words suggested he was courting the favor of a president who has frequently attacked the investigation and the people who conducted it.

"I don't trust Barr; I trust Mueller," House Speaker Nancy Pelosi told the Associated Press following Barr's testimony.

But it was the attorney general's stirring defense of the president Thursday, just prior to the report's release, that has thrust him right back into the public spotlight.

"President Trump faced an unprecedented situation," Barr told reporters, addressing the Mueller inquiry. "As he entered into office, and sought to perform his responsibilities as president, federal agents were scrutinizing his conduct before and after taking office and the conduct of his associates."

Offering an explanation for Trump's attempts to thwart the investigation, Barr said that there was "substantial evidence to show that the president was frustrated and angered by a sincere belief that the investigation was undermining his presidency, propelled by his political opponents, and fueled by illegal leaks."

Republicans largely defended Barr's performance, asserting that the attorney general acted appropriately to underscore the special counsel's findings.

"He's done everything he should do, and nothing that he shouldn't," said former Attorney General Michael Mukasey, who served under President George W. Bush. "The bottom line is that nothing got obstructed."

Mukasey also said that Barr was justified to make the final determination that Trump's conduct did not rise to obstruction.

"Hell, yes!" Mukasey said, endorsing Barr's intervention. "Somebody had to make the decision."

Robert Ray, a former federal prosecutor who investigated the Clinton-Whitewater scandal, also supported Barr, claiming that any criticism is politically motivated.

“I think that efforts to disparage the attorney general and his conduct while in office are despicable," Ray said. "It’s unfortunate that there are those who are attempting to undermine both his integrity and the integrity of his office for political purposes. It comes from... many lawyers and former federal prosecutors, who know better and are doing it anyway for political purposes, which I think is, again, despicable.”

Kupec, the Justice spokeswoman, said that the White House had nothing to do with staging Thursday's briefing, adding that Barr wanted to provide an overview of the report and explain the process for making it public.

Democratic leaders, however, blasted Barr, claiming that he "deliberately distorted" Mueller's findings.

“Special Counsel Mueller’s report paints a disturbing picture of a president who has been weaving a web of deceit, lies and improper behavior," according to a joint statement issued by Senate Minority Leader Chuck Schumer and Pelosi.

Recriminations also have followed from six Democratic House committee chairs who claimed that Barr had "mis-characterized" Mueller's findings.

Three Senate Democrats supported Barr's February confirmation as part of the 54-45 vote – Joe Manchin of West Virginia; Doug Jones of Alabama; and Krysten Sinema of Arizona – but as of Friday none have publicly indicated that they were reconsidering their votes.

While Pelosi has played down any effort to impeach the president, she nonetheless vowed that Congress would act.

"Congress will not be silent," she said.