What is the test for a plaintiff to sue a police officer for failing to stop a fleeing suspect?

Second, the plaintiff must show that the situation either presents the employee with a difficult choice of the sort that training or supervision will make less difficult or that there is a history of employees mishandling the situation. Whether to use deadly force in apprehending a fleeing suspect qualifies as a "difficult choice" because more than the application of common sense is required. Instead, police officers must adhere to the rule of Tennessee v. Garner, 471 U.S. 1, 105 S.Ct. 1694, 85 L.Ed.2d 1 (1985), that deadly force may constitutionally be applied to a fleeing suspect only when "the suspect threatens the officer with a weapon or there is probable cause to believe that he has committed a crime involving the infliction or threatened infliction of serious physical harm" and when, "where possible, some warning has been given." Id. at 11-12, 105 S.Ct. at 1701. A choice might also be difficult where, although the proper course is clear, the employee has powerful incentives to make the wrong choice.

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