Washington ? Eight federal prosecutors were fired last year because they did not sufficiently support President Bush’s priorities, Attorney General Alberto Gonzales’ former chief of staff says in remarks prepared for delivery to Congress today.

Separately, the Justice Department admitted Wednesday it gave senators inaccurate information about the firings and presidential political adviser Karl Rove’s role in trying to secure a U.S. attorney’s post for one of his former aides, Tim Griffin.

In a letter accompanying new documents sent to the House and Senate Judiciary committees, Justice officials acknowledged that a Feb. 23 letter to four Democratic senators erred in asserting that the department was not aware of any role Rove played in the decision to appoint Griffin to replace U.S. Attorney Bud Cummins in Little Rock, Ark.

Gonzales’ former chief of staff, Kyle Sampson, in remarks obtained Wednesday by The Associated Press, spoke dismissively of Democrats’ condemnation of what they call political pressure in the firings.

“The distinction between ‘political’ and ‘performance-related’ reasons for removing a United States attorney is, in my view, largely artificial,” he said. “A U.S. attorney who is unsuccessful from a political perspective … is unsuccessful.”

Democrats have described the firings as an “intimidation by purge” and a warning to remaining U.S. attorneys to fall in line with Bush’s priorities. Political pressure, Democrats say, can skew the judgment of prosecutors when deciding whom to investigate and which indictments to pursue.

Sampson, who resigned this month because of the furor over the firings, is to testify today before the Senate Judiciary Committee.

In his prepared testimony, he maintained that adherence to the priorities of the president and attorney general was a legitimate standard.

“Presidential appointees are judged not only on their professional skills but also their management abilities, their relationships with law enforcement and other governmental leaders and their support for the priorities of the president and the attorney general,” Sampson said.

He strongly denied Democrats’ allegations that some of the prosecutors were dismissed for pursuing Republicans too much and Democrats not enough in corruption cases.

“To my knowledge, nothing of the sort occurred here,” he said.

The White House said it will withhold comment on Sampson’s testimony until he testifies.