 In 1972, New York City Police Department Commissioner Patrick V. Murphy instituted a new policy that confined discretion in use of force to situations only where the officer's own life, or that of other people are in danger.This "defense of life" rule replaced the "fleeing felon rule".The 1985 Supreme Court decision, "Tennessee v. Garner" ruled that police may only use deadly force to prevent escape "when" the officer has probable cause to believe that the suspect poses a significant threat of death or serious physical injury to the officer or others.