Who's In Charge? The Party Leader, Legislative Institutions, and Party Preferences

How do political parties make decisions? Typically, scholars have focused on the formal party leader—the person who, in parliamentary systems, is in effect the party's candidate for Prime Minister—as the key actor. Powerful party leaders face a conundrum, however. If their parties are to govern or even to participate in the legislative process, they must delegate to agents. These agents—ministers, spokespersons, important committee members, or even unranked members who are recognized experts in specific policy areas—have their own policy preferences and priorities and, absent the threat of discipline, cannot be expected to toe a party line distinct from those preferences. At the same time, if being promoted within the party requires loyalty to the party line, no backbencher has incentive to reveal his preferences until he is in a position to use them to influence policy making or position taking. But agents who are forced to toe a policy line far from what they would like are unlikely to put a lot of effort into their service, as they gain little in policy terms from it. One solution is to give agents full leeway to set the party position in their issue areas (cf. Laver and Shepsle 1996), but then leaders have little to do and less policy influence. I resolve this dilemma using a formal model of party leadership that relies on incomplete information about the leader’s preferences to induce backbenchers sincerely to reveal their own preferences; the leader then can use information about backbencher preferences to choose agents who will define a party line close to—but not identical to—her own (cf. Kam et al. 2010).