In the case of Black v. United States in 1966, the Supreme Court ruled on a matter involving tax evasion and conspiracy charges against three defendants: Eugene B. Black, Sr., his son Eugene B. Black Jr., and their business associate Joseph W. Gantt Jr.. The Blacks owned several coal companies while Gantt was an attorney who had previously worked for the Internal Revenue Service (IRS). They were accused of creating fictitious loans to evade taxes and conspiring to defraud the government by impeding IRS functions. The defense argued that evidence used against them was obtained through illegal wiretapping by federal agents which violated their Fourth Amendment rights protecting against unreasonable searches and seizures. However, it was found that no such violation occurred as there wasn't any direct or indirect use of unlawful wiretap information during trial proceedings. The Supreme Court upheld their convictions with a unanimous decision stating that even if some evidence may have been gathered illegally, this did not automatically taint all other independently obtained evidence used in court.

In the dissenting opinion for Black v. United States, Justice Hugo L. Black argued that the majority's decision to uphold a conviction based on evidence obtained through unauthorized wiretapping violated Fourth Amendment protections against unreasonable searches and seizures. He contended that such practices were inherently invasive and unconstitutional, regardless of their potential usefulness in law enforcement or national security contexts. Furthermore, he criticized the court's reliance on "balancing" privacy rights against government interests as an inappropriate method for interpreting constitutional guarantees. Instead, he advocated for a strict interpretation of the Fourth Amendment which would categorically prohibit warrantless electronic surveillance by government authorities under any circumstances.