Loyalty and Disloyalty in the Mexican Party System

Abstract

AbstractWhy do politicians in Mexico switch parties? The party-switching literature suggests that politicians generally switch parties for office-seeking or policy-seeking motives, whereas literature on the Mexican party system suggests that switching may be related to party system realignment during the democratic transition. Using data on party switching across the political careers of politicians who served as federal deputies between 1997 and 2009, this study argues that party switching in Mexico can primarily be explained by the office-seeking behavior of ambitious politicians. Only in rare instances do politicians switch parties because of policy disagreements, and party system realignment fails to explain a large number of party switches. This article also suggests that the ban on consecutive re-election encourages party switching; after every term in office, Mexican politicians have the opportunity to re-evaluate their party affiliation to continue their careers.