After a U.S. appeals court upheld the University of Michigan law school’s affirmative action policy earlier this week, Harvard administrators applauded the decision but said they worry what might happen if the Supreme Court takes on an appeal of the case.

The Harvard Civil Rights Project, a research and advocacy organization based at the Law School, had filed a friend-of-the-court brief on the University of Michigan case supporting universities’ right to consider race as a factor in admissions.

The project’s leaders praised the 5-4 decision by the Sixth U.S. Circuit Court of Appeals for reaffirming a 1978 Supreme Court case that has since been considered legal precedent for permitting affirmative action.

“I think all the major universities and colleges in the country that have been employing affirmative action have been watching the law school case…and I hope this sends a strong signal to the universities that their policies are still valid and need to be continued,” said Angelo Ancheta, the project’s director of legal and advocacy programs and lead counsel on the brief.

University President Lawrence H. Summers also reacted favorably to the decision.

“I applaud the circuit court’s decision, which represents the endorsement of the kinds of admissions process that Harvard has used for years,” he said.

But Ancheta said he believes that if Harvard’s affirmative action policies were brought before the Supreme Court, the outcome would be uncertain.

“I certainly would want to think that they would [uphold the policies],” he said. “It would certainly be a close decision.”

The three white students who had been denied admission at Michigan and brought suit against the university have said they will likely appeal this week’s ruling to the Supreme Court.

If the nation’s highest court accepted the appeal and overturned the circuit court’s decision, universities across the country—including Harvard—would likely be forced to make drastic changes to their affirmative action policies.

Ancheta said he expects a decision from the high court by early fall on whether to hear the appeal, and he said the Civil Rights Project would file briefs in such a case.

He described himself as “cautiously optimistic” that the court would uphold the latest ruling but said he remains concerned by “the other decisions concerning race that have been coming out of the court.”

“I think it will be a close decision,” he said, adding that he expected the decision would come down to the swing votes of Justices Sandra Day O’Connor and Anthony M. Kennedy.

If and when the case heads to the Supreme Court, Ancheta said he hopes the University would submit a brief of its own in addition to the project’s filing.

“Given President Summers’ recent statement and the history of the University in affirmative action, I would hope,” he said. “Frankly, I think Summers has not been coming out as strongly as he should, but I think this is a chance to demonstrate that they really have a commitment to affirmative action.”

In an interview yesterday, Summers reaffirmed his commitment to affirmative action policies, although he declined to say whether Harvard would likely file a brief in the event of an appeal.

“I’m entirely comfortable with Harvard’s policy and Harvard’s rationale for that policy,” he said.

Indirectly, Harvard admissions policies played a part in both the circuit court decision on Tuesday and the 1978 Supreme Court case to which it referred, Regents of the University of California v. Bakke, which prohibited the use of quotas to achieve diversity but said race could be one criterion for admissions decisions.

Harvard’s methods for increasing diversity figured into the 1978 Bakke case as a model plan cited by Justice Lewis F. Powell in his concurring opinion.

The majority decision in the Michigan case, which is called Grutter v. Bollinger, referred to Powell’s discussion of the “Harvard plan,” which Powell said was legal because the University used race in admissions only in order to make its student body more diverse.

The majority opinion in the Michigan case compared the University of Michigan law school’s admission system to Harvard’s methodology as it operated in 1978.

“We find that the Law School’s consideration of race and ethnicity is virtually indistinguishable from the Harvard plan Justice Powell approved in Bakke,” the decision read.

But one of Tuesday’s dissenting opinions argued the 1978 case only referred to Harvard’s plan and did not actually rule on the legality of affirmative action policies at Harvard.

That opinion went on to compare Michigan’s system to Harvard’s “religious-conscious” admissions policies under former University President A. Lawrence Lowell in the early 20th century, which gave “preference in admissions to Gentiles as opposed to Jews…to produce a mixture of students in the school that was closer to the proportion that prevailed in society.”

Another case, concerning affirmative action in selecting University of Michigan’s undergraduate student population, is also pending decision by the appeals court.

—David H. Gellis contributed to the reporting of this story.

—Staff writer J. Hale Russell can be reached at jrussell@fas.harvard.edu.