United States Supreme Court
The application of physical force to the body of a person with intent to restrain constitutes a Fourth Amendment seizure, even if the person does not submit and escapes.
Torres v. Madrid held that police officers who shot a fleeing suspect to prevent her escape "seized" her within the meaning of the Fourth Amendment at the moment of the shot, even though she did not stop and drove away, setting the scope of Fourth Amendment protections for use of force.