Study Finds 1906 Naturalization Act Federal Standards Curbed Local Discretion and Bias in U.S. Citizenship Decisions

States that rely on city- and county-level officials to carry out public policy often gain from administrators’ local knowledge, but they also risk uneven or politically tilted decision-making. A new study by economists Abhay Aneja and Guo Xu examines whether federal standard-setting can rein in that discretion, using a pivotal moment in U.S. administrative history: the Naturalization Act of 1906.

Before 1906, much of the naturalization process—how immigrants’ applications for citizenship were evaluated and approved—was handled locally, leaving room for substantial variation from one place to another. The 1906 law changed that balance by introducing federal standards for citizenship applications, effectively tightening procedures and expectations for adjudication across jurisdictions. Aneja and Xu investigate what happened when these more uniform rules met a system that had long been shaped by local politics and patronage.

The authors draw on newly digitized U.S. census records spanning roughly three decades and covering more than five million immigrants. With this large dataset, they track naturalization outcomes over time and across cities, allowing them to compare patterns before and after federal standardization took hold.

One central finding is that the reform quickly reduced geographic inconsistency. After the 1906 standards were introduced, naturalization practices across cities moved rapidly toward one another, suggesting a swift convergence in how local offices processed and approved citizenship applications.

The study also documents a striking political pattern in the pre-reform era: naturalizations were about 30% higher during election years. That spike is consistent with the idea that local officials—potentially influenced by party machines or electoral incentives—accelerated citizenship grants when votes were at stake. After federal standards were implemented, however, this election-year surge vanished, indicating that the new administrative rules curtailed cyclical, politically timed naturalization.

To probe mechanisms, Aneja and Xu exploit another hallmark of the Progressive Era: municipal civil service reforms, which were adopted at different times in different cities and were designed to reduce patronage and weaken political control over administrative jobs. Using this staggered timing, they show that the decline in election-linked naturalization was most pronounced in cities that had not yet adopted civil service reforms. In other words, where local bureaucracies remained more exposed to political influence, federal standardization had the biggest disciplining effect.

Beyond the overall number and timing of naturalizations, the authors find that the reform altered who became a citizen. By eliminating the election-year bulge, the composition of newly naturalized cohorts shifted in measurable ways. Immigrants in the affected cohorts later earned about 7% more, were more likely to move into occupations that required citizenship, and chose more “Americanized” names for their children—signals consistent with deeper economic integration and assimilation.

Taken together, the evidence points to a broader lesson: when policy implementation is delegated downward, procedural standardization from above can reduce politically biased administration and make government action more uniform across places.

Why it matters

The study highlights how seemingly technical administrative rules can reshape political incentives and individual life outcomes. It suggests that federal standards can meaningfully constrain local discretion—especially where patronage politics are strongest—changing both the volume and the socioeconomic profile of people who gain access to citizenship-linked rights and jobs. Future debates over decentralization versus uniform national rules may hinge on this same trade-off between local flexibility and protection against biased implementation.