The Fourth Amendment to the Constitution prohibits “unreasonable searches and seizures” and requires the issuance of a warrant, based upon probable cause before certain types of searches can be conducted.
Some have argued that bulk government access to personal information for the purpose of conducting data mining or doing a link analysis is a “search” and that a warrant should be required before the data is collected. The Supreme Court addressed these questions in in a related context in two 1970-era cases: United States v. Miller and Smith v. Maryland. In both cases the question was, in effect, to what degree did an individual have a constitutional protection against the wholesale disclosure of information about him that had been collected by third-parties? And in particular, could an individual use the Fourth Amendment to prevent the government from using data it had received from a third party collector without a warrant?
The Supreme Court sided with government, developing what has come to be known as the “third party doctrine.” In Miller, the Court held that financial information voluntarily disclosed by an individual to a bank was not protected by the Fourth Amendment against subsequent disclosure to the government. Likewise, in Smith, the Court held that an individual’s toll telelphone records — records of the phone numbers called by the individual — were not protected against disclosure.
In effect, the Court adopted a gestational theory of anonymity—just as you can’t be a “little bit pregnant,” you cannot, according to the Court, be a “little bit public.” What you disclose to one third-party is fair game for everyone else.
Some scholars think that this result is the wrong one. Others think it is a correct interpretation of the Fourth Amendment. Either way, the academic debate is of no practical significance (unless you are writing a story about the debate), as there is no imminent prospect of a change in the Court’s view of the Fourth Amendment.
