The Effect of Legislature Size on Public Spending: A Meta-Analysis

In path-breaking work, Weingast et al. argue that there is a positive relationship between legislature size and inefficiency in public expenditures. Their proposition is currently known as the ‘law of 1/n’ and has been widely debated in political science and public administration. However, recent studies have questioned the validity of the theory. In this letter, we conduct the first meta-analysis that assesses the generality of the ‘law of 1/n’. Based on a sample of thirty articles, we find no robust evidence suggesting that legislature size has either a positive or a negative effect on government budgets. Yet, the aggregate results mask considerable heterogeneity. Our findings provide moderate support for the ‘law of 1/n’ in unicameral legislatures and in upper houses, but they also indicate that studies using panel/fixed-effects models or regression-discontinuity designs report negative public spending estimates. We find only limited evidence that electoral systems impact public spending, which suggests that proportional representation systems may not be more prone to overspending than majoritarian ones.