367 U.S. 643 (1961), argued 29 Mar. 1961, decided 19 June 1961, by vote of 5 to 3 to 1; Clark for the Court, black and Douglas concurring, Harlan, Frankfurter, and Whittaker in dissent, Stewart writing separately. Mapp finalized the “incorporation” of Fourth Amendment protections into the Due Process Clause of the Fourteenth Amendment. It required state officers to comply with Fourth Amendment standards when making searches and also extended the Fourth Amendment exclusionary rule to prosecutions in state courts.
In Wolf v. Colorado (1949), the Court had unanimously expanded the protections afforded by the Due Process Clause of the Fourteenth Amendment by concluding that it did prohibit “arbitrary intrusion” by state police. The Court divided 5 to 4, however, on the exact scope of such protection. Four justices read the Fourteenth Amendment as incorporating all the protections of the Fourth Amendment, thus requiring state officials to comply with Fourth Amendment standards. Justice Felix Frankfurter's majority opinion did not, however, go that far. Although he wrote that due process includes the “core of the Fourth Amendment,” he declined to spell out the exact scope of due process protections applicable to searches (p. 27). He did conclude, however, that the Fourth Amendment exclusionary rule that had been created in Weeks v. United States (1914) need not be applied in state court proceedings. (The exclusionary rule vote was 6 to 3; Justice Hugo Black joined the majority because he did not think the Fourth Amendment required exclusion.)
Wolf’s refusal to apply the exclusionary rule to the states was undermined eleven years later in Elkins v. United States (1960), in which a 5‐to‐4 majority concluded that the protections regarding searches afforded by the Due Process Clause were equivalent to those in the Fourth Amendment. (Justice Potter Stewart's majority opinion claimed Wolf had reached that conclusion; Frankfurter insisted in dissent that it had not.) Because Elkins was not a state prosecution itself, however, it did not provide a vehicle for overturning Wolf’s refusal to apply the exclusionary rule to the state. The very next year, however, Mapp provided such an opportunity.
Seven police officers had broken into and searched Dolly Mapp's home in Cleveland, Ohio. The police claimed they had a warrant but never produced it. They said an informant had told them that a person wanted for a recent bombing was hiding in Mapp's home and also that gambling paraphernalia was being hidden there. In fact, the police found neither during an extensive search. Instead, they found several allegedly obscene books and pictures; Mapp was convicted of possession of obscene literature and imprisoned. In affirming her conviction, the Ohio Supreme Court concluded that, although the search had been “unlawful,” Wolf nonetheless allowed the admission of the evidence.
In the Supreme Court, Mapp's attorney briefed and argued the case primarily on the obscenity issue. An amicus brief filed by the American Civil Liberties Union also argued, however, that the patently abusive search of Mapp's home by state officers also presented an opportunity to reconsider Wolf. Five justices seized that chance.
The voting in Mapp, however, was not a simple projection of the lineup a year earlier in Elkins. The opinion of the Court was written by Justice Tom Clark, who had dissented in Elkins. Clark had adopted the unusual posture of a provocateur with regard to Wolf—voting in several pre‐Mapp cases to press Wolf to its logical outcomes while hoping that (as he wrote in Irvine v. California, 1954) “strict adherence to the tenor of [Wolf] may produce needed converts for its extinction” (p. 139). On the other hand, Justice Stewart, who authored Elkins (and who later wrote that Elkins made it inevitable that the exclusionary rule would be applied to the states), refused to join the Court's opinion in Mapp because the exclusionary rule issue had not been properly briefed and argued. (During the oral argument, Mapp's attorney had stated that he was not asking the Court to overrule Wolf.)
As a result, the deciding vote in Mapp fell to Justice Black. Black was a staunch advocate of “incorporation,” but his view of the exclusionary rule itself was highly idiosyncratic—in Wolf he alone had questioned whether the Fourth Amendment required the Weeks exclusionary rule; in Mapp he alone concluded that the rule was required only by the Fourth and Fifth Amendments in combination. As a result, the opinion of the Court represented the views of only a four‐justice plurality regarding the basis for the exclusionary rule, but a five‐justice majority for its application to the states. Thus, although the extension of the exclusionary rule clearly should have been expected to generate political controversy, the prevailing justices apparently paid scant attention to judicial statecraft in deciding the issue in Mapp.
Justice Clark offered both “principled” and pragmatic reasons for extending the Weeks rule to the states. Although at one point he called the rule a “deterrent safeguard,” Clark's opinion largely paralleled the principled rationale offered for the rule in Weeks. He described the rule as being required by the Fourth Amendment and stressed that without the rule the Fourth Amendment would be reduced, in Justice Oliver Wendell Holmes's phrase, “to a form of words” (p. 648). Clark noted Justice (then Judge) Cardozo's complaint about the exclusionary rule that “the criminal is to go free because the constable has blundered.” He answered, “The criminal goes free if he must, but it is the law that sets him free” (p. 659).
Clark also argued that the pragmatic policy considerations in Wolf had proved to be unsound. He noted that the states without exclusionary rules had not developed any effective alternative means of dealing with unreasonable police searches; in fact, several additional state supreme courts had adopted state exclusionary rules in the years since Wolf, including the especially influential decision of the California Supreme Court in People v. Cahan (1955).
The three Mapp dissenters (who all had dissented in Elkins) continued to reject the incorporation doctrine and, largely for that reason, also rejected the extension of the Weeks exclusionary rule of the “soverign judicial system[s]” of the states.
See also Exclusionary Rule; Fourth Amendment.
— Thomas Y. Davies
