In the United States v. Troy case of 1934, the Supreme Court ruled on an issue related to tax evasion and fraud. The defendant, Mr. Troy, was accused of evading taxes by not reporting income from his bootlegging business during Prohibition in America (1920-1933). He argued that he could not be compelled to report illegal income as it would incriminate him under the Fifth Amendment's protection against self-incrimination. However, the Supreme Court disagreed with this argument and held that all income must be reported for taxation purposes regardless of its source - legal or illegal. This ruling established a precedent that individuals cannot use constitutional protections as a shield against paying taxes on illegally earned money.

In the dissenting opinion for United States v. Troy, Justice McReynolds argued that the majority's decision to uphold a conviction based on evidence obtained through wiretapping was fundamentally flawed. He contended that such methods of obtaining information were not only invasive but also violated an individual's right to privacy as protected by the Fourth Amendment. Furthermore, he expressed concern over potential misuse and abuse of this power by law enforcement agencies if left unchecked or unregulated. He believed it could lead to unwarranted intrusion into private affairs without any substantial justification or due process of law, thereby undermining civil liberties and constitutional rights in general. Thus, he disagreed with the court’s ruling allowing wiretap-obtained evidence in court proceedings.