monell doctrine

The Monell doctrine is a U.S. Supreme Court standard from the Monell v. Department of Social Services case (1978) that allows municipalities to be sued for constitutional violations if the violations resulted from an official policy, custom, or deliberate indifference in a failure to train or supervise employees. Unlike individual employees, the municipality itself cannot be held liable under a theory of vicarious liability (respondeat superior); instead, the plaintiff must demonstrate that the municipality's own official action or inaction was the cause of the constitutional injury.