INTRODUCTION

Since the mid-twentieth century, courts have begun to play a more important role in politics and policy-making in a range of polities. However, this “global expansion of judicial power” (Tate and Vallinder 1995) has been uneven: courts in many countries remain quite timid, and even the most crusading courts challenge the exercise of government power only selectively. As scholars have turned to examine the causes, contours, and consequences of the halting process of judicialization, the comparative judicial politics literature has blossomed. Since the main way courts become involved in politics is through their rulings, a central question in the literature concerns why courts decide politically crucial cases as they do.

Three main lines of argumentation have emerged to answer that question in Latin American cases: the strategic, the institutional, and the cultural approaches. The strategic approach suggests that judges' decisions are guided by opportunities and constraints in the broader political system, in particular those tied to the configuration and preferences of the elected branches (e.g., Helmke 2005) or the level of popular support a court enjoys (e.g., Staton 2006). Yet strategic accounts essentially identify the political conditions under which courts will be able to play a more salient role in politics and policy-making – for instance, in a context of political fragmentation or divided government. As scholars have begun to note (Hilbink 2009; Ingram 2009), just because courts can assume a more important political role does not mean that they will do so.