In the 1945 case ZAP v. United States, the Supreme Court ruled on a matter concerning double jeopardy and self-incrimination. The defendant, Zap, was convicted of selling distilled spirits without having paid the tax required by law. He appealed his conviction arguing that he had been subjected to double jeopardy because he had already been fined for non-payment of taxes on these same sales in a previous civil proceeding brought by the Internal Revenue Service (IRS). Furthermore, Zap argued that being forced to produce records during this earlier IRS investigation violated his Fifth Amendment right against self-incrimination. The Supreme Court rejected both arguments. It held that there was no double jeopardy as one action was criminal and another civil; they were two separate offenses under different statutes with distinct elements and purposes - one punishing illegal behavior while other recovering lost revenue due to evasion of taxes. Regarding self-incrimination claim, court stated it only applies when individual is compelled to testify against himself in a criminal case which wasn't applicable here as initial proceedings were civil not criminal.

In the dissenting opinion for ZAP v. UNITED STATES, Justice Frank Murphy argued that the majority's decision to uphold a conviction based on evidence obtained through wiretapping violated both statutory law and constitutional principles. He contended that federal agents had overstepped their authority by intercepting private communications without obtaining a warrant or consent from any party involved in those conversations. This, he believed, was not only contrary to Congress' intent when it passed legislation regulating wiretaps but also infringed upon individuals' Fourth Amendment rights against unreasonable searches and seizures. Furthermore, Justice Murphy expressed concern about the potential implications of this ruling for civil liberties if left unchecked; he warned that it could pave the way for more intrusive surveillance practices in future cases.