U.S. District Judge Royce Lamberth has raised many an eyebrow with his adjective-laden opinions in favor of the thousands of American Indians suing the government for mismanaging billions of their dollars.

On Tuesday, an appeals court panel was asked to decide whether his rulings show he is too biased to continue with the 10-year-old lawsuit.

"It is exceptionally rare for us to make this request we are making today, and we make it urgently," Assistant Attorney General Peter Keisler said, arguing that Lamberth should be removed from the case to "restore the appearance of fairness."

Lamberth, a Texas native and Reagan appointee, is well known for speaking his mind and setting high standards for the government when it appears in his courtroom.

Observers of the Indian trust case — called Cobell v. Norton — have said that after hearing years of arguments about the more than $100 billion in oil, gas, timber and other royalties Indians claim the government mishandled since 1887, Lamberth's frustration with the Interior Department is showing through.

But lawyers for the government argue he has gone far beyond that. On Tuesday, they said he has unacceptably charged the Interior Department with racism and that his opinions show he can no longer be objective.

The government petitioned to remove Lamberth after a July decision, in which he ordered the department to tell Indians that its information on trust assets may not be credible.

The 34-page opinion is a scathing condemnation of the department. An excerpt:

"Alas, our 'modern' Interior Department has time and again demonstrated that it is a dinosaur — the morally and culturally oblivious hand-me-down of a disgracefully racist and imperialist government that should have been buried a century ago, the last pathetic outpost of the indifference and Anglocentrism we thought we had left behind."

Keisler of the Justice Department told a three-judge panel of the U.S. Court of Appeals for the District of Columbia, "Even in cases involving convicted criminals, judges don't use language this way."

Lawyers for the Indians argued that Lamberth was not accusing the present-day Interior Department of racism. They said there is plenty of evidence that the government has repeatedly blocked Indians' efforts to get an accurate accounting of what they are owed.

If the appeals court removes Lamberth, "It will send a very clear message to the government that all their malfeasance ... is exonerated," said Keith Harper, lawyer for the Indian plaintiffs. "We think that would fundamentally undermine the appearance of justice and justice itself."

Lamberth has held Interior secretaries Bruce Babbitt and Gale Norton in contempt and more than once ordered the department to disconnect its computers from the Internet to protect Indians' records. Several of his rulings have been overturned on appeal, including Norton's contempt charge.

Norton, who stepped down from the department last month, watched from the back of the courtroom with other Interior officials Tuesday. She said she remains interested in the case but declined to comment further.

The appeals panel isn't expected to make a decision for several weeks.