In the case of ADAY et al. v. UNITED STATES, 1966, the Supreme Court ruled on whether certain evidence was admissible in a trial against two individuals accused of mail fraud and conspiracy to commit mail fraud. The defendants argued that their Fourth Amendment rights were violated when federal agents seized books and records from their business without a warrant or probable cause. However, the court found that while some documents were improperly seized under an overly broad search warrant, others fell within its scope and could be used as evidence in court. The decision hinged on whether these materials constituted "mere evidence" - items indirectly related to criminal activity - which at that time could not be legally seized without violating Fourth Amendment protections against unreasonable searches and seizures. The Supreme Court held that although some documents did constitute mere evidence and should have been excluded from trial due to improper seizure methods by law enforcement officials, other materials directly implicated in fraudulent activities were correctly admitted into evidence. This ruling underscored the importance of specificity in search warrants issued for businesses suspected of illegal activities but also highlighted potential limitations regarding what constitutes 'mere' versus incriminating evidentiary material.

In the dissenting opinion for ADAY et al. v. UNITED STATES, 1966, it was argued that the majority's interpretation of Section 1464 of Title 18 in this case was too broad and could potentially lead to an infringement on First Amendment rights. The dissenting justices believed that the language used in Section 1464 should be interpreted more narrowly to only apply to obscene material which is "utterly without redeeming social importance." They expressed concern over how a broader interpretation could result in censorship or self-censorship due to fear of prosecution under this law. Furthermore, they disagreed with the majority’s view that mailing obscene materials constituted a public nuisance because such materials were sent privately and not displayed publicly.