Members of the U.S. Supreme Court clashed over the value of university affirmative action policies, and pivotal Justice Anthony Kennedy raised the prospect that the court might put off issuing a broad ruling.

In a sometimes-heated argument Wednesday that ran more than 30 minutes beyond its allotted hour, the court's liberal wing defended the University of Texas program as a means of fostering diversity. Members of the court's conservative majority questioned whether racial preferences were warranted. Justice Antonin Scalia said that perhaps the university "ought to have fewer" minority students.

"One of the briefs pointed out that most of the black scientists in this country don't come from schools like the University of Texas," Scalia said. "They come from lesser schools where they do not feel that they're being pushed ahead in classes that are too fast for them."