Disproportionality in the representation and in the voter registration rates of Minority groups in the United States is widespread, but stronger when racial or ethnic minorities are electorally pivotal. We define this phenomenon strategic underrepresentation and show that for the period 1981-2020 levels of strategic underrepresentation of African American, Asian, and Latino voters in U.S. city politics are substantial. Underrepresentation is determined by the combination of several endogenous institutional features, starting from systematic disparity in voter registration, strategic selection of electoral rules, city’s form of government, council size, and pay of elected members of the council. We provide causal evidence of the strategic use of local political institutions in reducing electoral representation of minorities based on the U.S. Supreme Court narrow decision of Shelby County v. Holder (2013), which deemed unconstitutional Voting Rights Act (VRA) Section 4(b), removing federal preclearance requirements for a specific subset of U.S. jurisdictions.