March 29 (Bloomberg) -- Alberto Gonzales's ex-chief of staff contradicted his former boss, asserting that the attorney general was wrong in saying he wasn't involved in discussions on firing eight U.S. prosecutors.

Kyle Sampson, testifying today before the Senate Judiciary Committee, said he and Gonzales spoke at least five times over two years about plans to dismiss some federal prosecutors. Gonzales and then-White House Counsel Harriet Miers signed off on the final decision, Sampson said.

``I don't think the attorney general's statement that he was not involved in any discussions about U.S. attorney removals was accurate,'' Sampson told the committee in Washington. ``The attorney general was aware of this process from the beginning in early 2005.''

The Senate and House are investigating whether the prosecutors were dismissed last year for improper political motives such as interfering with criminal probes. Sampson's testimony further erodes Gonzales's credibility and gives critics calling for his ouster more ammunition, the senator leading the probe said at the close of the hearing.

``The credibility of the attorney general on this issue has been, I'd have to say, shattered, after what happened in that hearing room,'' said New York Democrat Charles Schumer, who previously called on Gonzales to resign. Sampson ``contradicted what the attorney general said repeatedly on important questions,'' the senator said.

Hindsight

In his testimony, Sampson said the firings were based on legitimate policy issues. Still, after answering withering questions from Democrats and some Republicans for nearly six hours at the witness table, Sampson told the panel that getting rid of the U.S. attorneys was a mistake.

``In hindsight I wish the department hadn't gone down this road at all,'' he said.

Sampson, 37, quit as Gonzales's chief of staff on March 12. The next day, Gonzales told reporters he ``was not involved in any discussions about what was going on'' with the firings. The attorney general said he delegated the project to Sampson, who didn't keep agency officials properly informed about the plans.

Justice Department spokesman Brian Roehrkasse said Gonzales had recently ``clarified his statements,'' saying in press interviews this month that he had occasional discussions with Sampson ``focused on ensuring that appropriate people were aware of and involved in the process.''

`Speak for Himself'

Sampson worked for Gonzales during most of the past six years and became the attorney general's chief of staff in September 2005.

White House spokeswoman Dana Perino, asked about Sampson's statements on Gonzales, said, ``I'm going to have to let the attorney general speak for himself.'' She said the president has confidence in Gonzales, who is scheduled to testify before the Senate Judiciary panel on April 17.

Sampson said today that he and Gonzales discussed the dismissals ``during the thinking phase'' and at ``the more final'' part of the process at the end of 2006.

``Then, ultimately, he approved the list,'' as did Miers, Sampson said.

Gonzales attended a meeting on the firings on Nov. 27, less than two weeks before most of the prosecutors were fired, Sampson added. Gonzales didn't mention the meeting when he spoke to the media on March 13.

`I'm Disappointed'

``I'm disappointed he didn't remember that in his statement,'' said Senator Jeff Sessions, a Republican from Alabama.

While calling the firings an embarrassment and apologizing to his former colleagues, Sampson said that top officials, including Deputy Attorney General Paul McNulty, played key roles in deciding which prosecutors to fire. None were ousted because of investigations they were pursuing, Sampson said.

``I'm not aware of any of the United States attorneys being asked to resign for the improper political purpose of influencing a case for political benefit,'' Sampson said. ``Some were asked to resign because they weren't carrying out the president and the attorney general's priorities.''

Sampson told the senators that ex-U.S. Attorney Carol Lam in San Diego was asked to leave partly because of her poor record prosecuting immigration cases, not because of her bribery probe related to ex-Representative Randall ``Duke'' Cunningham, a Republican who was sentenced to prison.

Patrick Fitzgerald

David Iglesias, the U.S. attorney in New Mexico whose office was investigating Democrats in a local corruption matter, also wasn't pushed out because of his cases, Sampson testified.

At one point, Sampson said, he suggested firing Patrick Fitzgerald, the U.S. attorney in Chicago who prosecuted ex-vice presidential aide Lewis ``Scooter'' Libby on perjury charges. Sampson said he made the suggestion to Miers and her deputy, William Kelley.

``They looked at me as if I had said something totally inappropriate, and I had,'' Sampson said.

Some Republicans on the committee said they were satisfied that the firings, while bungled, weren't improper.

``There's no evidence that the firings of these U.S. attorneys was done to impede a criminal investigation,'' said Senator John Cornyn of Texas.

Senator Arlen Specter, a Pennsylvania Republican, said after the hearing that Gonzales ``has many questions to answer and it starts off with his press conference statement that he wasn't involved.''

`State of Disrepair'

Earlier, during the hearing, Specter said, ``it is generally acknowledged that the Department of Justice is in a state of disrepair, perhaps even dysfunctional, because of what has happened.''

Separately, House Judiciary Chairman John Conyers, a Michigan Democrat, said the Justice Department agreed to make eight officials available for interviews with investigators starting today. They include McNulty; Michael Elston, his chief of staff; William Mercer, the acting No. 3 official at the agency, and Michael Battle, who formerly oversaw the U.S. attorneys.

Conyers said the interviews will be transcribed though kept ``confidential pending consultation with department officials.''

To contact the reporters on this story: Robert Schmidt in Washington at rschmidt5@bloomberg.net; Jay Newton-Small in Washington at jnewtonsmall@bloomberg.net.

Last Updated: March 29, 2007 19:01 EDT