ABSTRACT
In Katz v. United States, 389 US 347, the US Supreme Court voted seven–one that an illegal search existed under the Fourth Amendment's prohibition against unreasonable searches and seizures when law enforcement agents placed a wiretap without first obtaining a search warrant. The petitioner in Katz was convicted of transmitting wagering information by telephone from Los Angeles to Miami and Boston. In Smith v. Maryland, 442 US 735, the Court, citing Katz, addressed the issue of whether it was a permissible search if police, with the assistance of the phone company, tracked the telephone numbers dialed from a person's home. The Court affirmed the decisions by the court of appeals, which held that "there is no constitutionally protected reasonable expectation of privacy in the numbers dialed into a telephone system and hence no search within the Fourth Amendment is implicated by the use of a pen register installed at the central offices of the telephone company.
