CRIMES OF SUSPICION.

Requiring that officers have suspicion of specific crimes before they seize people during stops or arrests is a fundamental rule-of-law limitation on government power. Until very recently, the Supreme Court studiously avoided saying whether reasonable suspicion for street and traffic stops must be crime specific, and lower courts are sharply divided as a result. Statements made in Kansas v . Glover that the Fourth Amendment requires reasonable suspicion of a "particular crime " or of "specific criminal activity" may reflect an efort to rehabilitate this foundational principle, but crime specificity was not the Court 's focus in Glover. Meanwhile, Fourth Amendment scholars, even those closely focused on the nuances of probable cause and reasonable suspicion, have mostly ignored these developments. Police capitalize on this uncertainty, routinely conducting stops that are not tethered to any particular crime of suspicion. Even when the crime-control stakes for these general suspicion stops are low, they can lead to police violence. The deaths of Elijah McClain and Freddie Gray can be traced back to street stops based only on this sort offormless, general suspicion. This Article develops a comprehensive case for a Fourth Amendment crime specificity requirement applicable to street and traffic stops. The historical case is strong: the Framers clearly expected probable cause of a particular crime of suspicion for seizures, at least for elites, and those requirements have largely been preserved for arrests. It is also complicated. These formal rules developed alongside regular practices, which persisted long into the twentieth century before being held unconstitutional, of arresting those in poor and minority communities based on status or general suspicion. After marshaling historical evidence about arrests and crime specificity, this Article undertakes a thorough review of modern stop cases that raise these questions and analyzes relevant policy arguments, The impulses that often lead the Court to defer to law enforcement interpretations of suspicious facts in Fourth Amendment cases, do not apply to this question Of law. The crime of suspicion is a bright line, drawn by the legislature into the criminal code, and it is aline that police ojfcers are already expected to know. In practice, a robust crime-specificity requirement must be paired with decriminalization efforts. Otherwise, the current bloat of American criminal codes may limit the practical impact ofa crime-specificity requirement. Officers already exploit low-level offenses to conduct stops and intrusive Fourth Amendment searches. But there is potential here to rein in problematic street enforcement. During encounters where police are not quite sure ofwhat (ifany) crime they suspect, a crime-specificity rule requires that they remain in information-gathering mode and develop more specific suspicion before laying hands on a suspect. It is a requirement that makes space for de-escalation, for investigating alternative interventions, orfor officers to walk away. [ABSTRACT FROM AUTHOR]