A top aide to Attorney General Alberto Gonzales abruptly quit Friday, almost two weeks after telling Congress she would not testify about her role in the firings of federal prosecutors.
There was no immediate reason given, but Monica M. Goodling's refusal to face Congress had intensified a controversy that threatens Gonzales' job.
She resigned in a three-sentence letter to Gonzales, calling her five-year stint at Justice an honor and telling him, "May God bless you richly as you continue your service to America."
Asserting her Fifth Amendment right against self-incrimination, Goodling had rejected demands for a private interview with a House committee investigating the firings of eight U.S. attorneys.
She was senior counsel to Gonzales and was the department's White House liaison before she took a leave amid the uproar over the ousters.
The Justice Department declined comment on the resignation.
Goodling is at the center of the controversy because, as the bridge between the Justice Department and the White House, she may be best suited to explain how deeply Karl Rove and other members of President Bush's political team might have been involved in the firings. Congress also wants her to testify on Gonzales' role in light of his shifting explanations.
Her resignation came less than two weeks before Gonzales' own planned testimony to Congress, which may determine his fate as attorney general. Several Republican lawmakers have joined Democrats in calling for his resignation or dismissal over the firings and other matters at Justice.
Goodling's attorney, John Dowd, confirmed she had resigned but declined further comment.
Her resignation is the third by a Justice Department official who helped plan and coordinate the dismissals of the prosecutors, an effort that began shortly after President Bush won re-election in 2004.
Gonzales' chief of staff, Kyle Sampson, resigned under fire March 12 for orchestrating the firings.
Additionally, Mike Battle, the former director of the department's executive office of U.S. attorneys, announced several weeks ago that he was leaving to join a private law firm. Battle's resignation has not been linked directly to the controversy, although he helped notify some of the U.S. attorneys that they would be asked to leave.
"While Monica Goodling had no choice but to resign, this is the third Justice Department official involved in the U.S attorney firings who has stepped down," said Sen. Charles E. Schumer, D-N.Y., who was among the first senators to question the firings and the first to call for Gonzales' resignation.
"Attorney General Gonzales' hold on the department gets more tenuous each day," Schumer said in a statement.
Gonzales is also under fire for the FBI's improper and in some cases illegal prying into Americans' personal information during terror and spy probes.
Goodling's lawyers have asked Rep. John Conyers, chairman of the House Judiciary Committee, not to compel her to appear at a public hearing knowing of her intention to invoke the Fifth Amendment and refuse to answer questions.
Her lawyers have said such a hearing would be a perjury trap for her. They note allegations that Goodling misled Deputy Attorney General Paul McNulty before he testified to Congress about the ousters, causing him to give an incomplete and possibly inaccurate account.
Goodling's mother, Cindy Fitt of Osceola Mills, Pa., said the resignation had been anticipated. "She told me I'm to say 'no comment' for everything," the mother said in a brief telephone interview.