Electoral agency models suggest that government e¢ ciency is better when voters penalize poor
performance, and party competition is balanced. Uncertainty in the electoral mechanism dillutes
the incentive to produce e¢ ciently. We test this proposition on panel data on local governments.
The dataset includes a broad set of indicators on service output and quality, which facilitates
the measurement of cost e¢ ciency. We use historical data on local voting in national elections
to measure partisan bias, while electoral volatility is measured on past variations in neighboring
municipalities. The empirical analyses show that partisan bias lowers cost e¢ ciency, particu-
larly in municipalities with large electoral volatility.