SCRANTON, Pa. — A day after announcing his plan to resign, Attorney General Eric Holder Jr. returned to the scene of his first trial victory as a young law-and-order prosecutor. Visiting the U.S. attorney's office here, Holder was in his element, glad-handing and taking selfies with assistant U.S. attorneys, some of whom were as young as he had been when he prosecuted a corrupt businessman here 35 years ago.

But the arc of Holder's day in a way also reflected his own personal and professional trajectory as the country's chief law enforcement officer. And it underscored one of the most unusual transformations any attorney general has gone through in recent years.

Holder began the day by striding into the Walter E. Washington Convention Center in Washington, D.C., to give a speech at the Congressional Black Caucus's annual legislative meeting. He was greeted like a hero. Speaking passionately about voting rights, he was interrupted on several occasions with raucous ovations. Today the CBC is Holder's most loyal constituency, but for much of his career the group's liberal agenda would not have been a natural fit for him.

Those who knew Holder during his storybook rise in law and politics, from a junior prosecutor to a trial judge to the U.S. attorney for Washington, D.C., before becoming deputy attorney general under Bill Clinton, would hardly have predicted his evolution into the liberal reformist attorney general he has become.

Throughout most of his career, he held views that were moderate and conventionally liberal. As a judge meting out tough sentences for a city in the grips of a crack-fueled crime epidemic, he was known as "hold 'em Holder." And as a black lawyer rising through a still mostly white power structure, he wore his racial identity lightly and rarely if ever betrayed personal grievances. In temperament, Holder was mild and affable; he was hardly a crusader.

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U.S. Attorney General Eric Holder takes a selfie with a Dept. of Justice employee at the U.S. Attorney's office in Scranton, PA. (Courtesy of the Department of Justice)

But he will leave office at the end of the year with a record of progressive accomplishments that few other Obama cabinet members will likely be able to match. From reforming criminal sentencing to defending the legal rights of those in the LGBT community to forcing voting rights onto the national agenda, Holder can legitimately claim to be the most activist attorney general since Edwin Meese spearheaded Ronald Reagan's legal revolution in the 1980s. And he has been outspoken on racial issues, becoming a powerful weapon for President Obama, who has often been more reluctant to wade into the tricky waters of American identity politics.

In an interview in the William J. Nealon Federal Building in Scranton, it was strikingly clear that Holder has come to relish his reputation as a liberal reformer. "Some people get more conservative as they get older," he said. "I have become more aware of the need for positive change, and I was given a position where I could effectuate it."

While his department still prosecutes white-collar criminals — though not to the extent that many progressives would like — and puts away mobsters, Holder does not emphasize these aspects of his record. He spoke about being "galvanized" to confront the civil rights challenges of our era, whether it was reducing racial disparities in the criminal justice system or defending the rights of gays to marry. When asked by Yahoo News whether he believed there was an absolute constitutional right to gay marriage, he thought about it for a moment but then answered with an emphatic "yes."

And he repeatedly invoked an earlier attorney general, Robert F. Kennedy, whose legacy on civil rights enforcement made him an icon to the American left. Holder's effort to associate himself with Bobby Kennedy is another manifestation of his evolution. When he was growing up, it was Jack Kennedy — far more cautious on issues of race and civil rights than his younger brother — whom he had idolized. But as attorney general, he began to identify with Bobby's more activist, pugnacious approach.

"I gained an appreciation for how he was always pushing his older brother … to be more progressive, to be more daring when it came to social issues," Holder said in the interview. "Over time, I grew as attorney general and had a better sense of what I could do."

So what accounts for the change? I've covered Holder for more than 25 years, starting when he was appointed to the D.C. Superior Court. I believe there are several factors. One, as he told me in Scranton, was a realization that the time he had to make a difference was beginning to slip away. With his eye on posterity, the need to act became more urgent.

Eric Holder, then soon to be U.S. Attorney for the District of Columbia on August 2, 1993. (Photo by Tom Horan/The Washington Post/Getty Images)

But his closest friends and advisers point to another factor as well. Holder became a lightning rod for partisan Republican anger almost as soon as he took office — even before he started pursuing a more progressive agenda. He believed it was because he was a kind of stand-in for Obama, to whom he was personally close and who is also African American. Either way, Holder was increasingly under assault from Republicans in Congress, who took the unprecedented step of holding him in contempt.

Even worse than those legal proceedings, Holder believed that every time Congress hauled him up before one of its committees, his critics' real aim was to cast doubt on his judgment and intelligence and ultimately to humiliate him.

"What they were trying to do to him filled him with rage," said a close adviser of Holder's. "Look, Eric believes in all of the policies he's been pushing, but there's also an element of vendetta," the adviser continued. And from Holder's perspective, there was not much more the Republicans could do anyway — what did he have to lose by pursuing a more aggressive agenda?

Meanwhile, by the end of Obama's first term, the president was absorbing the reality that he could act more on issues he cared about since he was no longer facing re-election. Obama played a role in stiffening Holder's resolve. After the 2012 election, the president asked Holder to give him a memo with his top priorities for the second term. He wanted "blue sky" goals, without worrying about the political ramifications. Holder placed criminal justice reform at the top of that list. In a way, the memo had been prewired; in a series of quiet conversations over dinners or drinks in the White House, Obama and Holder had talked about their desire to deal with the crisis of incarceration for black men, caused in part by harsh, racially biased mandatory minimum sentences. Those conversations would ultimately lead to Holder's "Smart Crime" initiative, a comprehensive approach to making the criminal justice system fairer, and his push for Obama to grant clemency to thousands of low-level, nonviolent drug offenders sentenced under mandatory minimums.

But even with strong support of the president on many of these progressive policies, Holder still regularly ran into resistance from White House operatives who fretted over the political consequences of staking out such positions. (For some in the White House, Holder could never outlive the storm he caused by using the infelicitous phrase "nation of cowards" in a Black History Month speech shortly after he became attorney general.) When Holder said he wanted to give a speech in the wake of the acquittal of George Zimmerman, who had been accused of murdering Trayvon Martin, an unarmed black 17-year-old shot in a gated Florida community, the hand wringers at the White House balked. But Obama backed his attorney general. Still, when the speech was vetted by the White House, it came back with many suggested deletions. One line the White House wanted to remove, according to a source: "We can't sweep these issues under the rug."

President Barack Obama sits with Attorney General Eric Holder during the 32nd annual the National Peace Officers Memorial Service, Wednesday, May 15, 2013, on Capitol Hill in Washington, honoring law enforcement officers who died in the line of duty. (AP Photo/Pablo Martinez Monsivais, File)

Holder fought back and prevailed. He gave the speech, at the NAACP's annual convention in Orlando, Fla., in July 2013, and for the first time spoke openly about several instances when he was racially profiled, including the time he was stopped by the police in Georgetown running to catch a movie. He was a federal prosecutor at the time; the cops shone a floodlight on him and asked for identification.

Holder's willingness to push back hard against the White House politicos was a remarkable turnaround from the first term. During that period he had been brushed back repeatedly by Obama aides, who regarded him as a troublemaker with a political tin ear. His low moment was when he was forced under pressure to reverse his decision to try alleged 9/11 mastermind Khalid Sheikh Mohammed in a civilian court in Manhattan. Depressed by the death of his beloved mother, Miriam, the continuing lashings in the press over KSM and increasing isolation within the Obama administration, Holder seriously considered quitting. He was talked out of it by Valerie Jarrett, the senior adviser to Obama and Holder's most loyal patron in the White House.

Those who are closest to Holder point to one other key factor that may account for his transformation: the spine-stiffening influence of his wife of nearly 25 years, Dr. Sharon Malone. Intelligent, unafraid to stand up for what she believes in and occasionally steely, Malone has pushed and prodded her husband to resist his impulse to be a pleaser. When I interviewed her in the summer of 2009 for a profile I was writing of Holder for Newsweek, she did not mince words about her husband's character. "Eric sees himself as the nice guy," she told me over tea and cookies. "But when he leaves the nice guy behind, that's when he's the strongest."

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