Which landmark case addressed the legality of intercepting phone conversations?

The landmark case that addressed the legality of intercepting phone conversations is Olmstead vs US. This case, decided by the Supreme Court in 1928, involved the warrantless wiretapping of phone lines by federal agents who were collecting evidence on bootlegging operations. The Court ruled that the wiretaps did not constitute a violation of the Fourth Amendment right against unreasonable searches and seizures, primarily because the agents did not physically invade Olmstead's property.

This ruling was significant because it established a precedent that electronic eavesdropping did not necessarily require a warrant as long as it did not involve physical intrusion. However, it also set the stage for later challenges to privacy rights regarding wiretapping and communications surveillance, leading to evolving interpretations of the Constitution.

While the other cases listed pertain to different aspects of law and privacy, Olmstead vs US specifically focused on the interception of telephone conversations and how it intersected with Fourth Amendment protections at that time. This case ultimately laid the groundwork for later developments in privacy law, including the eventual landmark decisions that began to reinterpret the rights associated with electronic surveillance.