As a young lawyer at the Reagan Justice Department, Michael L. Williams was known for his aggressive prosecution of racial crimes.

He won awards for his handling of a case involving white supremacists in North Carolina, a case his supervisor said inspired death threats against him. He prosecuted a white supremacist in Idaho who had harassed the children of black and interracial families. He tried a Kentucky Klansman accused of firebombing the home of a black family and he won police brutality cases in Alabama and Arizona.

Now, as assistant secretary for civil rights at the Education Department, Williams, 37, finds himself in the middle of a very different kind of racial issue. His announcement Wednesday that colleges awarding scholarships solely on the basis of race would be denied federal funding has prompted bitter criticism from education and civil rights groups.

To those who have worked with him, there is no inconsistency in the two positions. As one of a handful of black conservatives who have served in the Reagan and Bush administrations, he is committed to fighting racial prejudice at the same time philosophically opposed to many of the conventional methods that have singled out minorities for special treatment.

"That Mike would be instrumental or involved in that decision is not a surprise to me," said Charles Cooper, an attorney in private practice who served as deputy assistant attorney general in Reagan's second term. "It certainly is in keeping with my understanding of his approach."

But civil rights advocates, who had seen Williams's appointment as a hopeful sign that the Bush Administration would depart from what they saw as the dismal record of the previous administration, the decision on college scholarships was a shock.

"Perhaps I misread him," said Suzanne Ramos, a lawyer with the Mexican-American Legal Defense and Educational Fund. "Perhaps he's a very good politician."

Ramos said Williams invited her to meet with him shortly after his confirmation last summer and, at the time, she was optimistic and encouraged at his knowledge and interest in bilingual education and other civil rights matters.

"We were impressed that he had actually called us and asked to meet with us," she said. "He was very personable, warm, friendly . . . . was optimistic about Mr. Williams." But his new policy on scholarships, she said, "was very dismaying."

Williams, who declined through a spokeswoman to be interviewed, joined the Justice Department's civil rights division in 1984. After four years in the division, he was a special assistant to Attorney General Dick Thornburgh and served as deputy assistant secretary for law enforcement in the Treasury Department before coming to the Education Department.

Williams began his career as a lawyer in his hometown of Midland, Tex., after earning his law degree, a master's and a bachelor's degree from the University of Southern California.

Those who have worked with Williams describe him as open, friendly, politically savvy, with a keen legal mind and a ready wit.

"His accomplishments and advancement in government {are} no accident," said Cooper. "He's got the tickets."

Others said his assignment to prosecute white supremacists and other cases of racial violence signalled that he enjoyed the confidence of his superiors.

"Those are tricky cases, even if the defendants are really bad actors," said Michael Carvin, who worked at the Justice Department with Williams and is now in private practice. "He had a good reputation."

At his confirmation hearing in May, Williams, who lives in Falls Church and is married to Donna Nelson Williams, a mechanical engineer, was asked by Sen. Paul Simon (D-Ill.) why he did not belong to the NAACP, the Urban League or other organizations "that have been championing the causes that your office really ought to be championing."

Williams answered that those groups did not have chapters in Midland, but that he had been one of three founders of a black student association at his university.

"What I am groping for is this," said Simon. "I want someone who is going to show the muscle and the backbone to really stand up and do a job."

"The question sort of goes to the fire burning in the belly," Williams responded. "It does and I think it has . . . . I think in the early part of my career, when I was a tad bit younger than I am now, I have shown that the fire has burned in the belly."