WASHINGTON - The civil rights lawyer whose path to a prominent post in the Obama administration was blocked by connections to the Mumia Abu-Jamal case has withdrawn as a nominee and joined a high-profile law firm.

Debo Adegbile, whose nomination to lead the Justice Department's civil rights division was derailed in March by a charged Senate vote, has joined Wilmer, Cutler, Pickering, Hale & Dorr L.L.P. as a partner, the firm announced Monday.

In an interview, Adegbile defended his work on Abu-Jamal's case, which drew a chorus of criticism led by Sen. Pat Toomey (R., Pa.) and the Fraternal Order of Police, and ultimately cost him a presidential appointment.

"Lawyers take an oath to uphold the laws of the land and certainly to uphold the Constitution," Adegbile said Monday night. "I don't regret the commitment to upholding the Constitution even in difficult circumstances."

Until Monday, he had not spoken publicly about his nomination, other than at Senate hearings. Presidential nominees, by tradition, do not speak to reporters while confirmation is pending.

Adegbile's defeat turned on one case during his tenure as head of the NAACP's Legal Defense Fund, which worked on Abu-Jamal's case as he fought the death penalty, decades after his conviction for the 1981 killing of Philadelphia Police Officer Daniel Faulkner.

As the head of the NAACP defense fund, Adegbile said, he reviewed legal briefs. His name is on three briefs, first in 2008 - years after a 2001 ruling dismissed Abu-Jamal's death sentence. The defense fund was fighting prosecutors' attempts to reinstate that penalty.

"It was a limited role, but a role that I don't shrink from," Adegbile said Monday.

He pointed out that federal judges ultimately agreed with his team's arguments that the death penalty should not be applied due to problems with the instructions given to the jury decades earlier.

"Capital cases are sensitive cases; they all involve very substantial heartache and, by definition, the loss of life, so they're not cases to be taken lightly," he said. "What the [Abu-Jamal] case stands for is that in the United states, even in the most difficult cases, it's possible to uphold the rule of law."

Adegbile was nominated to lead a Justice Department division that works to ensure voting rights, enforce laws protecting the disabled, and guard against employer discrimination, among other duties.

He will work instead in Wilmer Cutler's litigation department in New York, which includes litigation involving the government.

The vote on his nomination was charged with debates about justice, race, and sensitivity for the family of a slain policeman. Toomey argued that Adegbile not only defended a cop killer, but that the NAACP's team had helped glorify Abu-Jamal as he became a global cause célèbre. Philadelphia District Attorney Seth Williams joined in the criticism.

Toomey distributed documents highlighting statements of defense fund lawyers Adegbile supervised, and on the Senate floor read a searing plea from Faulkner's widow, Maureen, that said in part, "The thought that Mr. Adegbile would be rewarded in part for the work he did for my husband's killer is revolting."

Republicans and eight Democrats voted against him, scuttling President Obama's nomination in a 52-47 vote.

Toomey and Adegbile never met - "the opportunity wasn't offered," the former nominee said. Toomey's office declined to comment Monday.

Two Democrats from the Philadelphia region - Sens. Robert P. Casey of Pennsylvania and Chris Coons of Delaware - voted against Adegbile, along with other Democrats from conservative states who feared being linked to a lawyer who could be tied to an infamous criminal.

A former child actor on Sesame Street and a lawyer for 20 years, Adegbile, 47, said Monday he was surprised the Abu-Jamal case became such a focus. Beyond the briefs he signed, there was no evidence of his public advocacy for Abu-Jamal.

"You've never seen a public comment cited because none exist," he said. "I didn't anticipate that the focus would be on a case on which I had comparatively small involvement, particularly because I had rather substantial involvement in many important cases that go to the heart of American democracy." He cited two Voting Rights Act cases he argued in the Supreme Court.

"I did not understand that I would be voted down until perhaps moments before the vote," Adegbile said.

He called politics "a contact sport" but said he was not soured by the experience of seeing his legal career essentially reduced to a debate over one case.

"As somebody who has been engaged in civil rights," he said, "I'm crystal-clear that many people have sacrificed a lot more than I have to see that the civil rights of Americans are protected."