ABSTRACT

Before a police officer can use deadly force, they must have probable cause, a standard embedded in the Fourth Amendment to the U.S. Constitution. Probable cause develops from the totality of the circumstances, which is an objective assessment of the facts and circumstances known to the officer at the time he or she used force. That assessment must account for all the stimuli known to the officer through his or her five senses, coupled with information the officer personally knew or received from other sources before deadly force was used. The officer must not act out of fear alone, or unsubstantiated subjective perceptions; they must draw rational inferences from specific articulable facts that mix with their training, education, and experience to build the basis for action. Courts acknowledge that the assessment of an officer’s actions must be undertaken without the benefit of 20/20 hindsight vision. This means officers are granted leeway since probable cause is often determined during quickly evolving and dangerous investigations. Probable cause is evaluated using everyday common sense probabilities instead of exacting legal standards by scholars. This assessment is undertaken against prevailing legal standards and agency policy that establish proper and improper use of deadly force.