Answer:
Unconstitutional to tap a public phone without a warrant.
Explanation:
In Katz v. United States, 1967, the Supreme Court ruled that The Fourth Amendment protection should bring under its aegis the right to private conversation even electronically. In other words, the court ruled out that it was unconstitutional to wiretap electronic devices without a warrant.
Charles Katz was arrested for interstate gambling in 1965 with evidences from his telephonic conversation from a tapped telephone booth. However, his case became a much debated case on how far does the Fourth Amendment protection apply to.
Based on his case, the Supreme Court concluded that telephone booth becomes a private space when a person enters inside it, therefore it is unconstitutional to wiretap a telephone booth without a warrant.
