Choosing between Parliamentary and Presidential Governments.

Parliamentary and presidential systems dffer in the way citizens elect politicians in the executive power. In the first case they do it indirectly through the legislative power and in the second they do it directly. The main consequence of this is that ticket-splitting and divided governments appear in a presidential system. This may be seen as a problem or a opportunity by citizens because the trade-off between the loses in the political political bargainning process generated by cohabitation and the benefit of moderating the policy of extremist parties. This paper captures these features and compares both systems from a constitutional stage, i.e. when choosing ex ante what system to adopt from the standpoint of both citizens and political parties.