The powers of presidential office vary greatly across nations. In some, as in the United States, the president is both head of government and head of state. In others, as in Germany, the president is head of state (serving largely in a ceremonial role) and not head of government. Therefore, any analysis of the partisan nature of the office needs to consider whether the president is actually head of government or only head of state. If presidents do indeed head governments composed of political parties, one would expect that presidents should be linked to parties in their governments.

Given that expectation, one might be surprised to find that presidents were prohibited from engaging in party activities in about 20 national constitutions. The wording in constitutions for 11 countries—Albania (1998), Belarus (1996), Bulgaria (amended 2003), Chad (1996), Estonia (1992), Kazakhstan (amended 1998), Kyrgyzstan (amended 2003), Lithuania (1992), Niger (1999), Turkey (amended 2002), and Uruguay (amended 1996). All contain nearly blanket prohibitions against leading a party in government. (The 1996 Bangladesh constitution offers a different twist, stating that the president must appoint advisors from among those who are “not members of any political party or of any organisation associated with or affiliated to any political party.”)

It is more likely, instead, that nullifying any party role for the president reflects a romantic attempt to portray the president as “above” party politics. (Russian President Boris Yeltsin took that posture during his tenure— with unsatisfactory results.) To the extent that constitutions insulate government leadership from political parties, their framers deny that parties play a positive role in democratic government. Or perhaps the framers see the role but do not value it, which is even more troublesome.

Source: Political Parties and Democracy in Theoretical and Practical Perspectives

Legislatures in Presidential and Parliamentary systems

Parliamentary and presidential systems may differ in the ways that powers are allocated and exercised, and mixed systems may include features of both these systems. These differences can be seen in table 4.