In a unanimous decision, the Supreme Court ruled that an appeals court had used the wrong standard in sustaining a $4 million judgment against two Los Angeles County sheriff’s deputies.

The case arose from a confrontation in 2010. The deputies, searching for a criminal suspect, entered a shack without a warrant while its two occupants were napping. When one of them, Angel Mendez, picked up a BB gun, the deputies shot him and his pregnant companion, Jennifer Garcia. They suffered serious injuries, and part of Mr. Mendez’s right leg was amputated.

The United States Court of Appeals for the Ninth Circuit, in San Francisco, assumed that the use of force by the deputies had been reasonable once they were inside the shack. But the court said the deputies could nonetheless be sued because they had provoked the confrontation by entering the shack without a warrant, the New York Times reports.

Justice Samuel A. Alito Jr., writing for the Supreme Court, rejected that theory. “The rule’s fundamental flaw is that it uses another constitutional violation to manufacture an excessive force claim where one would not otherwise exist,” he wrote.

The case is now being sent back to United States Court of Appeals for the Ninth Circuit. The appeals court could rule the plaintiffs can sue the deputies for the warrantless entry.

The Association for Los Angeles County Deputy Sheriffs (ALADS) sent out a statement saying the membership is "grateful a unanimous United States Supreme Court rejected the "provocation rule" created by the 9th Circuit to judge use of force by deputies. This invented rule put the lives of deputies in danger by causing them to hesitate in using reasonable force to defend themselves for fear of later civil liability. The Supreme Court decision is a strong reaffirmation that any use of force will be judged solely based on the facts known to the deputies at the time force was employed."