In a 7-1 decision, the Supreme Court has vacated a ruling that upheld the University of Texas at Austin's affirmative action program, sending the case back to an appeals court.

Justice Kennedy wrote the opinion, finding that the Fifth Circuit appeals court in Texas should have applied strict scrutiny to the UT-Austin affirmative action program.

In October, the court heard a challenge to UT-Austin's admissions policy, which accepts the top 10% of students from every high school in the state, while considering race and other factors for students who aren't in the top 10%.

In a 2003 case involving the University of Michigan's law school, the high court said colleges can consider applicants' race to achieve a "critical mass" of minorities necessary for a diverse campus.

In the ruling on Monday, the high court ruled that the appeals did not scrutinize whether UT needed to consider race on top of its 10% policy in order to achieve that critical mass.

"The reviewing court must ultimately be satisfied that no workable race-neutral alternatives would produce the educational benefits of diversity," Kennedy writes. "Rather than perform this searching examination, the Fifth Circuit held petitioner could challenge whether the University's decision to use race as an admissions factor was 'made in good faith.'"

The Fisher case took an unusually long time to decide. Some experts speculated that was because Chief Justice John Roberts was issuing a sweeping ruling that would have done away with affirmative action. It's clear now that it may have taken a while to get all of the justices on board with a narrow ruling.

The sole justice who dissented was Ruth Bader Ginsburg. She pointed out that UT had reached the "reasonable, good-faith judgment" that its race-neutral 10% policy didn't achieve sufficient racial diversity and that it needed to explicitly consider race in admissions.

Elena Kagan recused herself from the case, most likely because she was involved with it when she was solicitor general.

Correction: A headline on an earlier version of this story said UT's affirmative action plan had been rejected. The error has been corrected.