Citizen suits are frequently cited as an essential legal innovation by virtue of their capacity to provide a backstop to lax or ideologically antagonistic administrations. Drawing on data from fifteen years of litigation under two prominent environmental statutes, we find little evidence that citizen suits effectively serve this role in practice. Instead, we find that limited resources and institutional barriers strictly limit the number of citizen suits filed annually against the federal government under two of the most litigated environmental statutes, the National Environmental Policy Act (NEPA) and the Endangered Species Act (ESA). While our findings do not negate the importance of citizen suits, they expose their limitations and the close alignment that exists between where suits are filed and local politics. Citizen suits mirror local values as they are overwhelmingly filed in jurisdictions in which concerns about the environment are the highest, and they are rare where public concern is lowest.

Our empirical findings lead us to reject the conventional model for citizen suits in favor of three alternative models that range from discrete, localized action to continuous lines of litigation over high-profile natural resources that can span decades. We find that the citizen suits under NEPA and the ESA that are covered by our study rarely target state or federal programs that are lax by national standards; instead, they serve a range of goals, large and small, that differ depending on the form of the suit (private enforcement actions, suits to perform nondiscretionary duties, or challenges to legally deficient agency action) and the programs and resources affected. Specifically, we find that citizen suits provide important constraints on agency discretion when environmental statutory mandates and the ideological outlook of presidential administrations diverge. Our findings also negate prominent critiques of citizen suits, most notably claims that citizen suits usurp government authority without the safeguard of political accountability and therefore are in need of vigorous gatekeeping by either executive branch officials or federal judges