In County of Los Angeles v. Mendez, published May 30, 2017, the U.S. Supreme Court reversed in part and remanded a bench-trial decision against the defendant county and two sheriff's deputies in a 42 U.S.C. section 1983 case alleging violation of the plaintiffs' 4th Amendment rights. While searching for a suspect for whom they had a felony arrest warrant, deputies entered a residence backyard without a search warrant. In the backyard was a one-room shack with a wooden door and a blanket over the doorway. The plaintiffs were napping on a futon inside. One of the plaintiffs kept a BB gun in the shack. The deputies entered the shack without knocking or announcing themselves. When a deputy entered, a plaintiff rose and picked up the BB gun so that it was pointing somewhat toward the deputy. The deputies shot the plaintiffs. The 9th Circuit Court of Appeals ruled that the deputies were entitled to qualified immunity on the alleged violation of the knock-and-announce rule under the 4th Amendment, but violated clearly-established law by entering the shack without a warrant. It affirmed the district court's conclusion that the deputies' use of force was reasonable under Graham v. Connor (1989) 490 U. S. 386, because the officers believed that a man was holding a rifle threatening their lives. But the district court and the 9th Circuit then applied its "provocation" rule, under which an otherwise-reasonable use of force is unreasonable violates the 4th Amendment if (1) the officer intentionally or recklessly provoked a violent response and (2) that provocation is an independent constitutional violation. The 9th Circuit concluded that the warrantless entry intentionally and recklessly brought about the shooting. It also concluded, alternatively, that the unannounced entry into the shack proximately caused the shooting.
The U.S. Supreme Court, in a unanimous opinion (except Justice Goresuch, who did not participate), rejected the provocation rule. The Graham v. Connor analysis is the "settled and exclusive framework" for analyzing whether a use of force complies with the 4th Amendment. A seizure that is reasonable under that framework is not a use of excessive force. Using another 4th Amendment claim to then impose liability for excessive force conflates 4th Amendment claims. Any other 4th Amendment claims must be analyzed separately.
The Supreme Court remanded the 9th Circuit's alternative theory that the shooting was proximately caused by one of the other 4th Amendment violations alleged. The 9th Circuit erred in finding the shooting was the proximate cause of the unannounced entry, because it ruled that the deputies were entitled to qualified immunity for violation of the knock-and-announce rule. The Supreme Court remanded for a determination whether the lack of a warrant caused the shooting.