nothing short of mandatory exclusion of the illegal evidence will compel respect for the federal law “in the only effectively available way — by removing the incentive to disregard it.” Elkins v. United States, 364 U. S., at 217.
Mr. Justice Black,
dissenting.
In 1937,
Nardone v.
United States, 302 U. S. 379, held that 47 U. S. C. § 605 forbids the introduction of intercepted and divulged telephone conversations in federal courts. In
Schwartz v.
Texas, 344 U. S. 199 (1952), this Court held, however, that the section does not forbid the use of such evidence in state criminal trials, saying: “[W]e do not believe that Congress intended to impose a rule of evidence on the state courts.” 344 U. S., at 203. I thought the holding in
Schwartz was correct then and still think so. The Court holds, however, that § 605 now compels state courts to exclude such intercepted telephone messages from state trials. The effect of this holding is to overrule
Schwartz v.
Texas. The Court’s holding is made despite the fact that Congress itself has not changed the section. Nor does
Mapp v.
Ohio, 367 U. S. 643 (1961), undermine
Schwartz as the Court intimates, for in
Schwartz we dealt, as we do here, with conduct that violates only a federal statute and so deserves only the sanctions contemplated by that statute. The Communications Act explicitly provides for penal sanctions, 47 U. S. C. § 501, and some civil remedies might be implied as a matter of federal law, cf. J.
I. Case Co. v.
Borak, 377 U. S. 426 (1964). But the creation by statute of a federal substantive right does not mean that the States are required by the Supremacy Clause to give every procedural trial remedy afforded by federal courts or that failure to afford such remedies renders the State “an accomplice in the willful transgression of 'the Laws of the United States.’ ”
Ante, at 386.