We often assume that those who wrote the Constitution understood its terms in a way that bears at least some similarity to the way we understand those terms today. This assumption is essential to the legitimacy of using Framing Era sources to inform the meaning of Constitutional provisions that regulate this system. This assumption is incorrect for one of the most important terms in criminal procedure. Probable cause meant something very different to the Framers than it means to modem lawyers. Probable cause was, as a practical matter, often nothing more than a pleading requirement for victims or officers who witnessed crimes. The modem notion of probable cause, an evidentiary threshold permitting a search or arrest that can be satisfied by the fruits of an officer's investigation, is a creation of the mid-nineteenth century. As with a number of Constitutional doctrines regulating the criminal justice system, we must look beyond the Framing Era to discover the origins of probable cause as it is understood by present-day lawyers.
Oliver, W. M. (2011). The Modern History of Probable Cause. Tennessee Law Review, 78 (2). Retrieved from https://dsc.duq.edu/law-faculty-scholarship/111