In the case of United States v. Dickerson (1939), the Supreme Court ruled on a matter concerning federal income tax evasion. The defendant, Mr. Dickerson, was accused of not reporting his full income for several years and thus evading taxes owed to the government. He argued that he had been entrapped by an undercover agent who encouraged him to invest in illegal activities which led to unreported earnings. However, the court found no evidence supporting this claim of entrapment and held that even if such encouragement occurred, it would not absolve him from liability for failing to report all taxable income earned through these investments or other means during those years under investigation. The Supreme Court upheld his conviction stating that taxpayers are obligated under law to fully disclose their incomes regardless of how they were obtained - legally or illegally - as long as they constitute taxable income according to U.S tax laws.

In the dissenting opinion for United States v. Dickerson, 1939, Justice McReynolds argued that the majority's decision to uphold a conviction based on evidence obtained through wiretapping was in direct violation of the Fourth Amendment rights against unreasonable searches and seizures. He contended that allowing such evidence would set a dangerous precedent where privacy could be easily invaded without any legal repercussions. Furthermore, he pointed out inconsistencies in previous rulings by highlighting cases where similar types of evidence were deemed unconstitutional and thus excluded from trial proceedings. In his view, this case represented an erosion of constitutional protections which should not have been permitted by the court.