A Baltimore library refused to admit Louise Kerr to a training program because she was black. Not that it had anything against blacks, but its patrons did. When Kerr launched a civil suit against the library alleging a violation of equal protection of the laws, the courts credited the library's claim that it had no racist purpose, but Kerr still prevailed-even though the case occurred before Title VII and Brown v. Board of Education. Here a neutral and generally applicable rule ("serve the patrons"), when coupled with particular facts about private parties (the white patrons dislike blacks), yielded an unconstitutional outcome. Jumping off from an analysis of that case, Professor Herzog shows that that structure recurs across a wide range of puzzling cases in constitutional law, some well-known, some not. Not only may the state not respond to some facts about private parties, sometimes it must actively combat them. So the structure raises questions about state action and legal rights. Herzog uses the structure to show that, despite conventional wisdom, state action is about responsibility, not causation. He then turns to legal rights and shows that neither purpose nor effects tests can explain the turns the law takes in these cases; instead, Herzog develops a new conception, that of the overextended rule.
Herzog, Donald J. "The Kerr Principle, State Action, and Legal Rights." Mich. L. Rev. 105, no. 1 (2007): 1-46.