The Supreme Court of the United States has held that the extension of the Age Discrimination in Employment Act to state and local governments was a valid exercise of Congress' powers under the commerce clause and was not precluded by virtue of tenth amendment constraints.
Equal Employment Opportunity Commission v. Wyoming, 103 S. Ct. 1054 (1983).
Mary M. O'Day,
Constitutional Law - Tenth Amendment - Commerce Clause - Application of ADEA to State and Local Governments,
Duq. L. Rev.
Available at: https://dsc.duq.edu/dlr/vol22/iss4/10