The Supreme Court on Thursday struck down affirmative action in college admissions, declaring race cannot be a factor and forcing institutions of higher education to look for new ways to achieve diverse student bodies.

The court’s conservative majority overturned admissions plans at Harvard and the University of North Carolina, the nation’s oldest private and public colleges, respectively.

Chief Justice John Roberts said that for too long universities have “concluded, wrongly, that the touchstone of an individual’s identity is not challenges bested, skills built, or lessons learned but the color of their skin. Our constitutional history does not tolerate that choice.”

Justice Clarence Thomas, the nation’s second Black justice who had long called for an end to affirmative action, wrote separately that the decision “sees the universities’ admissions policies for what they are: rudderless, race-based preferences designed to ensure a particular racial mix in their entering classes.”

Justice Sonia Sotomayor wrote in dissent that the decision “rolls back decades of precedent and momentous progress.”

Both Thomas and Sotomayor, the two justices who have acknowledged affirmative action played a role in their admissions to college and law school, took the unusual step of reading a summary of their opinions aloud in the courtroom.