1957—Three Cleveland police officers arrive at Dolly Mapp’s home seeking a suspect wanted in connection with a recent bombing. After Mapp refuses to admit them, the police forcibly enter and search the home and discover obscene materials. Mapp is convicted of possession of these materials. The Ohio supreme court rules that the search of the home was unlawful but that Mapp’s conviction resting on evidence resulting from the search is valid.

In Mapp v. Ohio (1961), the Supreme Court, by a vote of 5 to 3, overrules its own 1949 precedent that held that the Constitution does not require that evidence obtained in violation of the Constitution be excluded from criminal trials in state court. The Court instead applies to state criminal trials the exclusionary rule that it first imposed on federal criminal trials in 1914. In dissent, Justice Harlan (joined by Justices Frankfurter and Whittaker) concludes his analysis with this observation: “I regret that I find so unwise in principle and so inexpedient in policy a decision motivated by the high purpose of increasing respect for Constitutional rights. But in the last analysis I think this Court can increase respect for the Constitution only if it rigidly respects the limitations which the Constitution places upon it, and respects as well the principles inherent in its own processes. In the present case I think we exceed both, and that our voice becomes only a voice of power, not of reason.”