Comparative Politics/Presidential Systems, Parliamentary Systems, and Mixed Systems
As we have seen, democratic systems have elected officials. Most democratic states have many elected officials, who share power in predetermined ways. The two most popular models for sharing power amongst elected officials is the Presidential System and the Parliamentary System.
The Parliamentary System is the most popular model. In this system, a body of many representatives is elected by voters. This body might be called a House of Commons, a national assembly, a legislative assembly, a lower house, or any number of other names (for this discussion, we shall refer to it as a Legislature). Each member of the Legislature has one equal vote. The Legislature has the power to pass legislation, which has the force of law. To become law, the proposed law must receive the approval of the majority of the Legislature.
Usually at its first meeting after an election of new members, the Legislature chooses from amongst its membership an Executive body, i.e., the officials in charge of making sure that legislation is enforced. This body is usually called a cabinet, but is sometimes called a Council of Ministers. Each member of the cabinet usually has a specific portfolio, over which he/she is responsible: finances, foreign policy, defence, agriculture, transport, etc. The chairman of the cabinet is the most powerful person in a Parliamentary system, and is usually given the title of Prime Minister (aka., "chancellor", "premier", or "first minister").
The Legislature also chooses the "President" of the state, who is usually a ceremonial figurehead for the state (called the head of state). Sometimes, the President is given the duty of settling deadlocks in the Legislature over the choice of members of the Cabinet. (Some states maintain a king or queen as their ceremonial head of state. Such states are called "constitutional monarchies", while systems with presidents are called "republics". There is little difference between these two types of states in practice).
Most members of the Legislature are part of a faction within the body that wishes to pursue a common political agenda. This is called a political party. If one political party constitutes a majority of the members of a Legislature, then that party can dictate who gets chosen for the Cabinet and what legislation gets approval. This is called majority government. The leader of the majority party automatically becomes Prime Minister, and as long as he/she maintains the confidence of his/her party, he/she can dictate who is in the cabinet and what legislation gets passed. This makes the Prime Minister a very power official. The Prime Minister can even decide to dissolve the Legislature and call a new election.
Parliamentary systems are prevalent in western Europe, as well as the former colonies of Great Britain.
The Presidential system was first developed by the framers of the United States Constitution in the 1780s. The framers disapproved of the way in which the Prime Minister of Parliamentary systems could accumulate so much power. They therefore developed a system designed to spread power more evenly over many different elected officials. This is known as the separation of powers.
In a typical presidential system, the president is not purely symbolic. Not only is the President the head of state, but is also in charge of naming the members of the cabinet (called "administration" in the United States). The President also has some powers specifically mandated by the constitution, particularly in foreign policy and defence. The president is not chosen by the legislature, but directly elected by the voters. The President is not allowed to be a member of the legislature.
The legislature (or congress in the United States), the leader of the majority party does not automatically become the Prime Minister. In fact, in many presidential systems, the position of Prime Minister does not exist; the President instead chairs the cabinet. The legislature holds elections at fixed intervals (usually every four years), instead of being dissolved by a Prime Minister. Because the majority party of the legislature does not control the executive, political parties play a less important role in a Presidential system, and members of the same party may often vote differently in the legislature.
The Presidential system is used in the United States and states strongly influenced by the United States, such as Mexico.
Mixed systems incorporate attributes of the Parliamentary system and Presidential System. Often, these mixes result in a directly elected President with powers equivalent to a Prime Minister. For instance, in France, the President is directly elected by the people every five years. The President of France may dissolve the National Assembly. If the President has the following of a majority of the National Assembly, then he may appoint the Cabinet; if he does not have the following of the National Assembly, then he may only appoint members of the Cabinet who are responsible for foreign policy and defence.
Mixed systems have proven popular amongst relatively new democracies, such as Russia, the Ukraine, and Iraq, since they give a lot of power to the President.