Technology has enhanced the government's ability to intrude through wiretapping, eavesdropping, and other electronic means. In Olmstead v. United States, 277 U.S. 438 (1928), the Court, over Justice Brandeis' famous dissent, took the narrow approach that the Fourth Amendment only protects a person against searches or seizures of "material things"--his person, his house, his papers and effects--but not his words overheard on telephone wires outside his home. Eventually in Berger v. New York, 388 U.S. 41 (1967), and Katz v. United States, 389 U.S. 347 (1967), the Court concluded that the Fourth Amendment does protect against the seizure of words by electronic means even when the government does not physically trespass or intrude on a person's private space.
But technology marches on, and in Kyllo v. United States, 533 U.S. 27 (2001), the Court had to address the Fourth Amendment implications of the government's warrantless use of thermal imaging devices outside a person's home to determine what is occurring inside the person's home.
Last week in City of Ontario, California v. Quon the Court addressed the Fourth Amendment in the context of another technological advance: text messaging. While the case raised the narrow issue of whether a police officer had any rights of privacy in the text messages sent and received on his alphanumeric pager issued by the police department, the Court recognized this new technology was forcing it to enter unchartered territory.
"The judiciary risks error by elaborating too fully on the Fourth Amendment implications of emerging technology before its role in society has become clear." The very ubiquity of cell phone and text messages raises new and serious constitutional questions regarding privacy. Rather than sweeping pronouncements on privacy rights, "prudence counsels caution" by the Court until society's use of rapidly changing communications--and society's privacy expectations regarding those communications--become clearer.
Quon is an important statement on how an appellate court proceeds when it is asked to make policy determinations without knowing what technology will emerge and how society will use that technology. The subtext is that the Court understands new technology will emerge. The case can be found here.