Milliken v. Bradley
In Milliken v. Bradley, 433 U.S. 267, 291 (1977), the U.S. Supreme Court reiterated that local government may be sued for damages in federal court:
"The Tenth Amendment's reservation of nondelegated powers to the States is not implicated by a federal-court judgment enforcing the express prohibitions of unlawful state conduct enacted by the Fourteenth Amendment."
This was a 5-4 decision written by Chief Justice Warren Burger, with Justice Byron White joining the liberal wing in dissent.
This case is often cited for a principle of federalism:
"No single tradition in public education is more deeply rooted than local control over the operation of schools; local autonomy has long been thought essential both to the maintenance of community concern and support for public schools and to quality of the educational process." Id. at 741 (citing Wright v. Council of the City of Emporia, 407 U.S. 451, 469 (1972)).