In the case of Clancy et al. v. United States (1960), the appellants were convicted for conspiracy to defraud the U.S government by submitting false claims through their company, which was a subcontractor on military contracts during World War II. The Supreme Court upheld these convictions despite arguments from the defendants that they had been denied due process because some evidence used against them had been obtained via an illegal search and seizure operation conducted by FBI agents without warrants or consent. The court ruled that while such actions would have violated Fourth Amendment rights if carried out by law enforcement officers, in this instance it was private citizens who discovered and handed over incriminating documents to authorities - thus no constitutional violation occurred. Furthermore, even though one of those individuals later became an FBI agent himself, his status at time of discovery determined legality of his actions under exclusionary rule doctrine. This decision reinforced principle that Fourth Amendment protections apply specifically to governmental action; private searches do not trigger same scrutiny unless there is significant state involvement or direction involved.

In the dissenting opinion for Clancy et al. v. United States, it was argued that the majority's decision to uphold a conviction based on evidence obtained through warrantless wiretapping violated Fourth Amendment protections against unreasonable searches and seizures. The dissenting justices contended that this ruling expanded government surveillance powers in an alarming way, potentially infringing upon citizens' privacy rights without proper checks or balances. They also expressed concern about the potential misuse of such unchecked power by law enforcement agencies and cautioned against setting a dangerous precedent where constitutional rights could be easily overridden in pursuit of criminal investigations. Furthermore, they disagreed with the majority's interpretation of existing laws regarding wiretapping, arguing instead for stricter adherence to established legal principles concerning search warrants and due process.