universities and other private businesses, which are free to practice affirmative action unless prohibited by federal statute or state law. Several important affirmative action cases to reach the Supreme Court have concerned government contractors—for instance, Adarand Constructors v. Peña (1995) and City of Richmond v. J.A. Croson Co. (1989). But the most famous cases have dealt with affirmative action as practiced by public universities: Regents of the University of California v. Bakke (1978), and two companion cases decided by the Supreme Court in 2003, Grutter v. Bollinger and Gratz v. Bollinger. In Bakke, the Court held that racial quotas are unconstitutional, but that educational institutions could legally use race as one of many factors to consider in their admissions process. In Grutter and Gratz, the Court upheld both Bakke as a precedent and the admissions policy of the University of Michigan Law School. In dicta, however, Justice O'Connor, writing for the Court, said she expected that in 25 years, racial preferences would no longer be necessary. In Gratz, the Court invalidated Michigan's undergraduate admissions policy, on the grounds that unlike the law school's policy, which treated race as one of many factors in an admissions process that looked to the individual applicant, the undergraduate policy used a point system that was excessively mechanistic. In these affirmative action cases, the Supreme Court has employed, or has said it employed, strict scrutiny, since the affirmative action policies challenged by the plaintiffs categorized by race. The policy in Grutter, and a Harvard College admissions policy praised by Justice Powell's opinion in Bakke, passed muster because the Court deemed that they were narrowly tailored to achieve a compelling interest in diversity. On one side, critics have argued—including Justice Clarence Thomas in his dissent to Grutter—that the scrutiny the Court has applied in some cases is much less searching than true strict scrutiny, and that the Court has acted not as a principled legal institution but as a biased political one. On the other side, it is argued that the purpose of the Equal Protection Clause is to prevent the socio-political subordination of some groups by others, not to prevent classification; since this is so, non-invidious classifications, such as those used by affirmative action programs, should not be subjected to heightened scrutiny. See also References External links Original Meaning of Equal Protection of the Laws , Federalist Blog Equal Protection: An Overview, Cornell Law School