The limitation of the doctrine of “reasonable expectation of privacy” in the Fourth Amendment of United States Constitutional Law and its implications for the protection of privacy and security in relation to surveillance-type information collection under the Constitution of Japan

Abstract

“Reasonable expectation of privacy theory” in the Fourth Amendment of the United States Constitution is in confusion due to the prevalence of surveillance-type information collection by public authorities. This is mainly because of a gap between whether people have an expectation of privacy with regard to each piece of information collected and whether that collection invades their privacy. In Japanese Constitutional Law, the idea of “rights to self-information control” is allegedly dominant as privacy protection. This idea is closely related to “reasonable expectation of privacy theory” in that the range of protection relies on social context corroborated by “expectation.” As the range of “expectation” changes according to technological developments, however, it is not meaningful to ask whether people have an expectation of privacy with regard to each piece of information collected. Thus, it is required to establish a framework to inquire whether surveillance-type information collection is implemented in a manner that leads to people’s private lives being exposed with its scale and capacity.