Law Commons^™

The Plausible And The Possible: A Bayesian Approach To The Analysis Of Reasonable Suspicion, W. David Ball

Faculty Publications

The United States Supreme Court uses the wrong approach to analyze reasonable suspicion. The Court asks whether, if criminal activity were afoot, an officer would be likely to see what she saw (e.g. furtive gestures or flight from police). The ultimate question we are interested in, however, is whether, given what the officer saw, her conclusion about criminal activity was reasonable. These two questions are different. Even if it is highly likely that an officer would make a set of observations when criminal activity is afoot, it does not follow that criminal activity is itself highly likely when an officer …