Legislative Voting and the Economic Theory of Politics

Empirical studies of legislative voting have multiplied since the mid-1970s. Early work [13] distinguished two modes of representation: Delegates, who vote as voters want, and Trustees, who use their own judgment. More recently, researchers have considered only delegates, claiming that legislators who use their own are shirking. Following principal-agent theory, representatives are conceived as conduits through which citizens transmit and express interests. Empirical work on this question, however, has found that the legislator's ideology explains more variation in vote choices than is explained by measures of constituent interest. The seeming contradiction has led some [9; 10; 17] to reject the economic of legislator behavior as erroneous. The truth is that no such theory has ever been fairly stated, much less tested. Estimating equations have been ad hoc, and the usual approach to measuring has imposed correlation between the equation error and an explanatory variable [8]. In both cases, the result is