Shawn HublerSoumya Karlamangla and Stephanie Saul

In a statement, Mr. Newsom said that “merit, skill and hard work” should determine college admissions. “The California Dream shouldn’t be accessible to just a lucky few,” he said, “which is why we’re opening the door to higher education wide enough for everyone, fairly.”

Schools with legacy preferences have argued that they have not compromised their high standards and that children of alumni who are admitted are highly qualified, or they would not have been accepted.