In June 22, 2018, the Supreme Court made a landmark decision, which held in a 5-4 decision that The Government’s acquisition of Carpenter’s cell-site records was a Fourth Amendment search. Prior to Carpenter, the Supreme Court held that a person had no legitimate expectation of privacy in regards to dialed telephone numbers conveyed to telephone company voluntarily turned over to third parties, and therefore a search warrant was not required to obtain the information. This legal theory is known as the third-party doctrine, established by the Supreme Court case Smith v. Maryland (1979). In this paper, we discuss the third-party doctrine and analyze each justice’s opinion about the Supreme Court Decision of Carpenter case.
