Many §1983 plaintiffs seek to establish municipal liability for the violation of constitutional rights based on the enforcement of a municipal custom or practice. This column analyzes “custom or practice” municipal liability. We will explain the importance of this issue, explore the meaning of “custom and practice,” and identify the types of evidence that may be admissible to prove a municipal custom or practice.

In its landmark decision in Monell v. N.Y.C. Department of Social Services, 436 U.S. 658 (1978), the U.S. Supreme Court held that municipalities may be sued under §1983, but not on the basis of respondeat superior. A municipality may be liable under §1983 only for its own wrongs, which means when the violation of the plaintiff’s federal rights resulted from the enforcement of a municipal policy or practice. “[I]t is when execution of a government’s policy or custom …  inflicts the injury that the government as an entity is responsible under §1983.” Id. at 694.