Physical entry into the home is the chief evil the Fourth Amendment was designed to prevent. Absent consent or exigent circumstances, the police need a warrant to enter a person's home. But what if the police intentionally make an unconstitutional entry into a home and, once inside, reasonably fearing they are in imminent danger of serious physical harm, employ deadly force? Under the circumstances the use of force was reasonable, but it may not have been necessary if the police had not conducted the unconstitutional entry. The Ninth Circuit had formulated the “provocation doctrine” for this type of situation. Under this doctrine the officer could be held liable for injuries from the use of force which was otherwise reasonable, but which was a foreseeable consequence of his intentional or reckless unconstitutional search.

In County of Los Angeles v. Mendez, 137 S. Ct. 1539 (2017), the U.S. Supreme Court, in a unanimous decision written by Justice Samuel A. Alito Jr., recently overturned the provocation doctrine on the ground that it was inconsistent with the court's Fourth Amendment excessive force jurisprudence. The court held that whether officers who conduct an unconstitutional search are liable for injuries from their subsequent use of force depends upon the application of traditional proximate cause principles. As we will see, applying proximate causation in these circumstances is easier said than done.

Background

Deputy sheriffs in California were searching for a parolee-at-large named Ronnie O'Dell, who was considered armed and dangerous. They learned from a confidential informant that O'Dell was seen at a home owned by Paula Hughes, and that Angel Mendez and his wife lived in a shack in the backyard of her home. After failing to find O'Dell in Hughes's home, the officers, without a warrant and without knocking and announcing their presence, entered the Mendez shack. Angel Mendez was holding a BB gun closely resembling a small caliber rifle, which he kept for use on rats and other pests. When the officers entered the shack, the BB gun was pointed “somewhat” at Deputy Sheriff Conley. “Deputy Conley yelled 'Gun!' and the deputies immediately opened fire, discharging a total of 15 rounds. Mendez and [his wife] 'were shot multiple times and suffered severe injuries,' and Mendez's right leg was later amputated below the knee.” 137 S. Ct. at 1545 (citation omitted). O'Dell was not in the shack or anywhere on the Hughes property.