Attorney General Eric Holder, who has endured a rocky tenure as the nation's top lawyer, is hardly hiding his ambition these days — it's all about cementing his legacy.

When Holder announced that he was halting mandatory minimum prison sentences for nonviolent drug offenders, it capped an aggressive period for the man who once declared that his department's Civil Rights Division was again "open for business."

First, Holder slammed state "Stand Your Ground" laws in the wake of the not-guilty verdict in the killing of Florida teenager Trayvon Martin. Then, he vowed to challenge any changes states make to their voting laws after the Supreme Court overturned the centerpiece of the Voting Rights Act. With the focus on prison sentences, Holder found a third issue on which he could become the public face of the Obama's administration's response on civil rights issues.

By scrapping mandatory minimums, which are vastly unpopular with liberals, Holder not only won points with Democrats but also enhanced his clout by once again sidestepping Congress.

"And people accused us of being overly ambitious," a high-ranking official in President George W. Bush's Justice Department told the Washington Examiner. "You can argue for the merits of what they are doing, but this is yet another example of Holder unilaterally imposing his will. He's going to be in overdrive until the day he leaves."

Holder has moved to the issue of minority rights after arguably his roughest patch at the Justice Department.

When it was discovered that his department had targeted reporters at the Associated Press and Fox News — part of the Obama administration's unparalleled crackdown on the spilling of government secrets — Holder even faced calls from some on the left to step down. Holder claimed to be in the dark about the Associated Press episode, stoking frustration at a time when the White House was already under fire for government overreach.

Though Holder is expected to step down during Obama's second term, his latest actions seem to nix the idea of a swift exit.

"He wants to leave with some sort of record that defines him," said Stephen Hess, a senior fellow at the Brookings Institution and a former adviser to Presidents Gerald Ford and Jimmy Carter. "You can say in the first term Holder was mostly pushed around. It wasn't so much his record but how to respond to others. He now seems to have a strong psychological motivation to do more."

Republicans counter that Holder is easily definable.

They point to the botched Fast and Furious gun-trafficking case as an example of his tendency to sweep aside politically inconvenient controversies. And GOP leaders say Holder is basically ignoring the Supreme Court by demanding that states clear new voting laws with the Justice Department.

But focusing on mandatory minimum prison sentences could prove a politically shrewd move. Liberals and civil libertarians agree that nonviolent offenders needlessly drive up prison costs, potentially giving the attorney general the type of bipartisan cover that could ease reforms.

"The administration's involvement in this bipartisan issue is a welcome development," Sen. Rand Paul, R-Ky., said. "Now the hard work begins to change the law to permanently address this injustice [of mandatory minimum sentences]."

But some said not to read too much into the new friendliness between Holder and the libertarian-leaning wing of the Republican Party.

"Let's not get carried away," a Paul staffer told the Examiner. "It's still Eric Holder we're talking about."