Tennessee v. Garner, 471 U.S. 1 (1985), is a civil case in which the Supreme Court of the United States held that, under the Fourth Amendment, when a law enforcement officer is pursuing a fleeing suspect, the officer may not use deadly force to prevent escape unless "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."

It was found that the use of deadly force to prevent escape is an unreasonable seizure under the Fourth Amendment, in the absence of probable cause that the fleeing suspect posed a physical danger. Legal scholars have expressed support for this decision stating that the decision had "a strong effect on police behavior" and specifically that it can "influence police use of deadly force."

At about 10:45 p.m. on October 3, 1974, Memphis police officers Leslie Wright and Elton Hymon were dispatched to answer a burglary call. Officer Hymon went behind the house as his partner radioed back to the station. Hymon witnessed someone running across the yard. The fleeing suspect, 15 year old Edward Garner, stopped at a 6 ft 0 in (1.83 m) chain-link fence. Using his flashlight, Hymon could see Garner's face and hands, and was "reasonably sure" that Garner was unarmed.

After Hymon called out "police, halt", Garner began to climb the fence. Believing that Garner would certainly flee if he made it over the fence, Hymon shot him. The bullet struck Garner in the back of the head, and he died shortly after an ambulance took him to a nearby hospital. Ten dollars and a purse taken from the burglarized house were found on his person.

Hymon acted according to a Tennessee state statute and official Memphis Police Department policy authorizing deadly force against a fleeing suspect. The statute provided that "if, after notice of the intention to arrest the defendant, he either flee or forcibly resist, the officer may use all the necessary means to effect the arrest."

Garner's father then brought suit in the United States District Court for the Western District of Tennessee under the Civil Rights Act of 1871, 42 U.S.C. § 1983, naming the City of Memphis, its mayor, the Memphis Police Department, its director, and Officer Hymon as defendants. The District Court found that Hymon's actions were authorized by the statute. On appeal, the United States Court of Appeals for the Sixth Circuit remanded for reconsideration of municipal liability under Monell v. New York City Dept. of Social Services. The district court found the statute and Hymon's actions were constitutional. The Court of appels reversed: if the killing of a fleeing suspect is a "seizure" for the purposes of the Fourth Amendment, it is only constitutional when it is reasonable. The Court then found that based on the facts in this case, the Tennessee statute failed to properly limit the use of deadly force by reference to the seriousness of the felony.

Justice White wrote for the majority, first agreeing with the Sixth Circuit's determination that apprehension by use of deadly force is a seizure, then framing the legal issue as whether the totality of the circumstances justified the seizure. In order to determine the constitutionality of a seizure, White reasoned, the court must weigh the nature of the intrusion of the suspect's Fourth Amendment rights against the government interests which justified the intrusion.

The use of deadly force against a subject is the most intrusive type of seizure possible: "The suspect's fundamental interest in his own life need not be elaborated upon." White held that the state failed to present evidence that its interest in shooting unarmed fleeing suspects outweighs the suspect's interest in his own survival, and society's interest in a judicial determination of guilt and punishment.