winset of the status-quo is the intersection of the preferred sets of all veto players
(represented by the gray area in Figure 1). Any proposal within W(SQ) defeats the
status-quo, while policies outside the winset are by definition unenforceable.
Figure 1
In the following pages, we use this simple computational model of veto players in
presidential regimes to integrate three levels of analysis: games among institutions (the
Presidential Powers and Policy Stability
The comparative literature has conventionally classified constitutional law-
making powers accorded to the executive as proactive and reactive (Shugart and Carey
1992; Shugart and Mainwaring 1997). Proactive legislative powers allow presidents to
unilaterally “establish, or attempt to establish a new status quo†(Shugart and Haggard
2001, 72) while reactive powers allow them to defend the status quo from any changes
attempted by the legislature. The evidence of the impact of presidential powers on policy
stability is somewhat mixed. Johnson and Crisp (2003) claimed that constitutional decree
authority was not significantly related to the adoption of neoliberal reforms, while
Nielson (2003) showed that stronger legislative powers favored the provision of public
goods (in the form of lower tariffs) in middle-income presidential democracies (Nielson
2003). In turn, Cox and Morgenstern have argued that presidential powers play an
important role when the president is politically weak but less so when the president has
vast support in congress (Cox and Morgenstern 2002).
3
Convention