In Katz v. United States, the Supreme Court ruled that tapping a public phone without a warrant violated the defendant's: A. right to avoid self-incrimination. B. freedom of assembly. C. protection against double jeopardy. D. protection against unreasonable search and seizure.

D. protection against unreasonable search and seizure.<br /><br />In Katz v. United States, the Supreme Court held that the government's eavesdropping on a public phone booth without a warrant constituted a violation of the Fourth Amendment, which protects against unreasonable searches and seizures. The Court emphasized the importance of privacy and established the principle that the Fourth Amendment protects people, not just places.