The dominant approach toward Fourth Amendment doctrine over the past half-century has centered on the notion of civil convention.(199) This is perhaps sensible, as the Fourth Amendment itself speaks in the language of reasonableness, and in the real world at least, what is reasonable is a function of society’s norms and practices.(200) The general understanding of the rule is that there is a twofold requirement, first that a person has exhibited an actual (subjective) expectation of privacy and, second, that the expectation be one that society is prepared to recognize as ‘reasonable’.(201) These two prongs reduce the concept of social convention, and indeed, courts rarely assess the two prongs independently.(202)
It is true that the reasonable expectation of privacy test answers only the threshold question of what constitutes a search, but this formulation masks the true importance of the inquiry.(203) Because warrantless searches are presumptively unreasonable and therefore violate the Constitution, the central question in the context of any warrantless search is whether a search occurred at all.(204)
Although the Supreme Court has adopted a presumptive warrant requirement, it has also carved out a multitude of exceptions and exemptions.(205) Many of these exceptions are premised on notions of reasonableness, and their limits are correspondingly bounded by what is reasonable.(206) Thus it is clear that social convention has become the defining ideal of the Fourth Amendment – the source of authority that gives reasonableness its shape.(207)
One useful example, consent has long been an exception to the warrant requirement.(208) Yet when a truly difficult consent case came before the Supreme Court, the Court held that the answer must be divined by looking to “widely shared social expectations.”(209) The Court thus treated social convention as the determinant of reasonableness.(210)
This method, probably dominant within the modern judiciary, interprets the Fourth Amendment by looking primarily to social norms and behavior.(210) Law enforcement officials are held to these standards if they do not obtain a warrant, and actions that fall beyond reasonable social convention and deemed unconstitutional.(211) In the next post we will discuss the method of interpretation known as “Originalism”.