THIS CASEBOOK contains a selection of U. S. Court of Appeals decisions that analyze and discuss issues surrounding municipal liability under 42 U.S.C. § 1983. * * * It is well established that "under § 1983, local governments are responsible only for 'their own illegal acts.' .... They are not vicariously liable under § 1983 for their employees' actions." Connick v. Thompson, 563 U.S. 51, 60, 131 S.Ct. 1350, 179 L.Ed.2d 417 (2011) (quoting Pembaur v. Cincinnati, 475 U.S. 469, 479, 106 S.Ct. 1292, 89 L.Ed.2d 452 (1986) (emphasis in Pembaur)); see, e.g., Board of County Commissioners v. Brown, 520 U.S. 397, 403, 117 S.Ct. 1382, 137 L.Ed.2d 626 (1997) ("We have consistently refused to hold municipalities liable under a theory of respondeat superior."); City of Canton v. Harris, 489 U.S. 378, 392, 109 S.Ct. 1197, 103 L.Ed.2d 412 (1989); Monell v. Department of Social Services of the City of New York, 436 U.S. 658, 665-83, 691, 98 S.Ct. 2018, 56 L.Ed.2d 611 (1978). Plaintiffs who seek to impose liability on local governments under § 1983 must prove, inter alia, that the individuals who violated their federal rights took "'action pursuant to official municipal policy.'" Connick v. Thompson, 563 U.S. at 60, 131 S.Ct. 1350 (quoting Monell, 436 U.S. at 691, 98 S.Ct. 2018). * * * "Official municipal policy includes" not only "the decisions of a government's lawmakers," but also "the acts of its policymaking officials, and practices so persistent and widespread as to practically have the force of law.... These are 'action[s] for which the municipality is actually responsible.'" Connick v. Thompson, 563 U.S. at 61, 131 S.Ct. 1350 (quoting Pembaur, 475 U.S. at 479-80, 106 S.Ct. 1292 (emphasis ours)). Thus, a § 1983 plaintiff need not prove that his injury was caused by an explicitly stated municipal rule or regulation. Further, a municipality may be liable even for its inaction if, in its failure to act, it "'exhibit[ed] deliberate indifference to constitutional deprivations caused by subordinates.'" Cash v. County of Erie, 654 F.3d 324, 334 (2d Cir. 2011) (quoting Amnesty America, 361 F.3d at 126), cert. denied, 565 U.S. 1259, 132 S.Ct. 1741, 182 L.Ed.2d 528 (2012); see generally City of Canton, 489 U.S. at 388-92, 109 S.Ct. 1197. Outlaw v. City of Hartford, 884 F. 3d 351 (2nd Cir. 2018)