It protected rights by letting race be an admissions factor.
In Regents of the University of California v. Bakke (1978), the Supreme Court's decision gave some credence to Allan Bakke's claim that the University of California at Davis had practiced some amount of reverse discrimination in denying him admittance to the medical school because he was not an economically or educationally disadvantaged member of one of four racial/ethnic groups eligible for their special admission program. But the Court was careful to note that race could be considered as a factor (among many factors) in college admissions, with schools needing to practice great care in doing so. Having a basic quota system, such as UC Davis reserving 16 spots out of 100 each year, was considered discriminatory.