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Mapp v. Ohio 367 U.S. 643 (1961)

MAPP v. OHIO 367 U.S. 643 (1961)

Mapp v. Ohio brought to a close an abrasive constitutional debate within the Supreme Court on the question whether the exclusionary rule, constitutionally required in federal trials since 1914, was also required in state criminal cases. Mapp imposed the rule on the states.

wolf v. colorado (1949) had applied to the states the fourth amendment's prohibition against unreasonable searches, but it had not required state courts to exclude from trial evidence so obtained. Mapp 's extension of Wolf was based on two considerations. First, in Wolf the Court had been persuaded by the rejection of the exclusionary rule by most state courts; by 1961, however, a narrow majority of the states had independently adopted the rule. Second, the Wolf majority was convinced that other remedies, such as suits in tort against offending officers, could serve equally in deterring unlawful searches; time, however, had shown that such remedies were useless. "Nothing can destroy a government more quickly than its failure to observe its own laws," wrote Justice tom c. clark for the Court, "or worse, its disregard of the charter of its own existence."

inMapp v. Ohio the Court asserted emphatically that the exclusionary rule was "an essential part" of the Fourth Amendment and hence a fit subject for imposition on the states despite "passing references" in earlier cases to its being a nonconstitutional rule of evidence. Yet, in some hazy phrasing, the opinion also suggested that the Fifth Amendment's right against self-incrimination was the exclusionary rule's constitutional backbone. Equally confusing was the Court's characterization of the rule as "the most important constitutional privilege" (that is, personal right) guaranteed by the Fourth Amendment while at the same time pointing to the rule's deterrent effect as justification for its imposition. More recently, the Court has settled on deterrence as the crucial consideration, and thus has refused to apply the rule in situations, such as grand jury proceedings in calandra v. united states (1974), where in the Court's view the deterrent effect is minimal.

Three dissenters, in an opinion by Justice john marshall harlan, expressed "considerable doubt" that the federal exclusionary rule of weeks v. united states (1914) was constitutionally based and argued that, in any event, considerations of federalism should allow the states to devise their own remedies for unlawful searches.

(Unlike the well-entrenched federal exclusionary rule, which has gone well-nigh unchallenged on the Court from the beginning, controversy concerning the rule for the states has continued unabated, both on and off the Court, since Mapp was decided.)

Jacob W. Landynski

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