Judge John G. Roberts Jr., tapped Tuesday night by President Bush as his nominee to replace Sandra Day O'Connor on the U.S. Supreme Court, has an unusual distinction among the jurists considered for the post: extensive experience representing colleges.

In several of those cases, he tried to limit the ability of people to sue colleges. Roberts is known as a conservative legal thinker, but he also participated in discussions on preparing a brief, filed by a coalition of higher education associations, defending the use of affirmative action.

In between holding key judicial and legal posts in Republican administrations, he was a partner at Hogan & Hartson, a Washington law firm with a major practice in higher education. Roberts won cases before the Supreme Court on behalf of Gonzaga University (limiting the rights of students to sue colleges over privacy-law violations) and the National Collegiate Athletic Association (excluding it from Title IX coverage as an association).

"John is one of the most brilliant lawyers I have ever worked with," said Martin Michaelson, a partner prominent in the college and university practice at Hogan & Hartson. "He was very effective on a number of occasions for higher education." Roberts is "fairly described as conservative," said Michaelson, "but I have a high regard for him even though we haven't always agreed on political matters."

Experts on education law said that Roberts, if confirmed, would bring a solid understanding of colleges to the nation's highest court. "You'd be hard pressed to find anyone [in senior judicial circles] with that level of experience on higher education," said Kermit L. Hall, president of the State University of New York at Albany and editor in chief of the Oxford Companion to the Supreme Court of the United States. "I feel very good about having someone who understands higher education and how it works."

Currently, Roberts is a judge on the U.S. Court of Appeals for the District of Columbia Circuit. In that role, he wrote a unanimous decision for a three-judge panel that rejected a National Labor Relations Board decision to recognize a faculty union at LeMoyne-Owen College, in Tennessee. The college relied on Supreme Court precedent -- specifically a 1980 ruling rejecting faculty rights to unionize at Yeshiva University -- to argue that professors at private colleges should not engage in collective bargaining.

The decision by Roberts did not state that it would be impossible for a union at a private college to win recognition. Rather, the decision faulted the NLRB for not stating why it was ignoring certain past rulings in similar cases. "The NLRB may have an adequate reason for the result in reached in this case," Roberts wrote. "We cannot, however, assume that such an explanation exists until we see it."

Representing Gonzaga University before the Supreme Court, as a lawyer at Hogan & Hartson, Roberts won a major victory for colleges worried about being sued. The Supreme Court ruled that individuals did not have the right to sue colleges for violating the Family Educational Rights and Privacy Act, widely known by its acronym FERPA. Many higher education groups backed Gonzaga in the case.

The Gonzaga case arose from a suit by a graduate who said he was unable to get a teaching job because the university had reported to a teacher-certification office an allegation that the graduate had sexually assaulted another student.

In 1999, Roberts helped the NCAA win a Supreme Court battle. In that case, the Supreme Court ruled that the association was not covered by Title IX -- even though the NCAA is supported financially by member institutions that are covered by the law.

Roberts has not always been a winner with the Supreme Court. In 2002, he represented two administrators at Jefferson Community College, in Kentucky, who were sued by an adjunct faculty member when his contract was not renewed, apparently over offensive comments he had made in the classroom. The administrators tried to have the suit against them dismissed, and Roberts handled an appeal to the Supreme Court, which declined to hear the case.

Sheldon E. Steinbach, vice president and general counsel of the American Council on Education, has worked with Roberts on many cases and praises him as someone with "a superior understanding, interest and knowledge about both K-12 and higher education."

Steinbach said that Roberts helped in the discussions at Hogan & Hartson about an amicus brief that the ACE organized on behalf of dozens of higher education groups in defense of affirmative action. The brief -- strongly supportive of affirmative action -- was filed in two Supreme Court cases, decided in 2003, about admissions policies at the University of Michigan.

"I don't know what his stand is on affirmative action. But I do know that he played a role in the amicus brief" and that his "intellectual firepower" strengthened the arguments, Steinbach said.

Prospects for Roberts in the Senate confirmation process were unclear last night. For much of Tuesday, rumors flew in Washington that another appeals court judge would be nominated for the Supreme Court opening. Several liberal groups issued statements Tuesday night raising questions about his views, and several conservative groups issued statements praising his views -- but higher education was not the focus of his fans or detractors.