In the case of Taglianetti v. United States (1968), Phillip Taglianetti appealed his conviction for conspiracy to bribe a federal officer, arguing that evidence obtained through wiretapping by state police and used in his trial was unconstitutional under the Fourth Amendment. The Supreme Court disagreed with him, ruling 5-3 that since there was no participation or knowledge on part of any federal official about the illegal surveillance until after it had occurred, and because it did not involve communication affecting national security interests, its use did not violate the defendant's constitutional rights. Therefore, they upheld his conviction.

In the dissenting opinion for Taglianetti v. United States, Justice William O. Douglas argued that the majority's decision to uphold a conviction based on evidence obtained through illegal wiretapping was fundamentally flawed and violated Fourth Amendment protections against unreasonable searches and seizures. He contended that allowing such evidence to be used in court would incentivize law enforcement agencies to continue engaging in unconstitutional practices, as they could still use any illegally obtained information to secure convictions. Furthermore, he disagreed with the majority's assertion that excluding this type of evidence from trial would not deter future violations of privacy rights by government officials. Instead, he believed it was essential for courts to reject all unlawfully acquired evidence in order to maintain public trust and respect for constitutional liberties.