Delegates or Trustees? A Theory of Political Accountability

When do elections induce politicians to act as delegates, and when do they induce them to act as trustees? To answer this question, we develop a model of political accountability in which politicians vary in both their policy preferences and their competence. We show that elections are more likely to induce politicians to behave as trustees when uncertainty about incumbent policy preferences is low. Otherwise, voters are often unable to credibly commit to vote retrospectively, and incumbents are electorally rewarded for the positions they take as opposed to the outcomes that they generate. Our theoretical results help us understand a number of empirical puzzles, such as why voters sometimes re-elect politicians who are known not to share their preferences. The model also yields predictions about several other factors that determine whether elected officials will act as delegates or trustees. Suppose the public believes that a particular country is helping a terrorist organization acquire weapons of mass destruction. And suppose that the president’s intelligence strongly suggests otherwise. If the president fails to attack the regime, she runs the risk of appearing out of step with public opinion. Yet, if the president attacks, she runs the risk of appearing inept if it is later revealed that the accused country was innocent. What will she do – attack or not attack? The answer to this question depends on how the public reacts when an executive’s policy choice indicates that she shares the public’s policy preferences, yet, at the same time, suggests that she has poor judgement. If voters reward the executive with re-election, they encourage her to act as their delegate, i.e., she has an electoral incentive to ignore her expert judgement about which policies promote the general welfare, and instead simply to pursue whatever policies happen to be popular at the moment. Alternatively, if voters punish the executive for having chosen an initially-popular policy that turned out to be inappropriate, they encourage her to act as their trustee, i.e., she has an electoral incentive to pursue policies that she believes promote the general welfare, based on her expertise. Thus, whether the public evaluates the executive based on the policies she chooses or the outcomes that her policies generate determines whether elections encourage her to behave as a delegate or a trustee. In this research note, we determine when voters will judge politicians on the basis of policies and when they will judge politicians on the basis of outcomes. In doing so, we are able to determine how voters’ actions affect the form of representation provided by elected executives. Our analysis focuses on two factors – the competence and preferences of politicians – that political theorists who study delegate and trustee representation have long recognized as playing a central role in elections. For example, in his critique of delegate representation, J.S. Mill (1962 [1861], 241) focused on the need for wise leaders, but noted that preferences also matter since voters “cannot be expected to postpone their particular opinions, unless in order that they be served by a person of superior