In a parliamentary system, such as India, the head of state usually has mostly ceremonial powers, with a separate head of government. However in some parliamentary systems, like South Africa, there is an executive president that is both head of state and head of government. Likewise, in some parliamentary systems the head of state is not the head of government, but still has significant powers, for example Morocco. In contrast, a semi-presidential system, such as France, has both heads of state and government as the de facto leaders of the nation (in practice they divide the leadership of the nation among themselves). Meanwhile, in presidential systems such as the United States, the head of state is also the head of government.
An independent nation state normally has a head of state, and determines the extent of its head's executive powers of government or formal representational functions.
In terms of protocol: the head of a sovereign, independent state is usually identified as the person who, according to that state's constitution, is the reigning monarch, in the case of a monarchy; or the president, in the case of a republic.
Among the different state constitutions (fundamental laws) that establish different political systems, four major types of heads of state can be distinguished:
In a federal constituent or a dependent territory, the same role is fulfilled by the holder of an office corresponding to that of a head of state. For example, in each Canadian province the role is fulfilled by the lieutenant governor, whereas in most British Overseas Territories the powers and duties are performed by the governor. The same applies to Australian states, Indian states, etc. Hong Kong's constitutional document, the Basic Law, for example, specifies the chief executive as the head of the special administrative region, in addition to their role as the head of government. These non-sovereign-state heads, nevertheless, have limited or no role in diplomatic affairs, depending on the status and the norms and practices of the territories concerned.
World's parliamentary states (as of 2019): Republics with an executive president elected by a parliament Parliamentary republics Parliamentary constitutional monarchies in which the monarch usually does not personally exercise power Presidential republics, one-party states, and other forms of government
In parliamentary systems the head of state may be merely the nominal chief executive officer, heading the executive branch of the state, and possessing limited executive power. In reality, however, following a process of constitutional evolution, powers are usually only exercised by direction of a cabinet, presided over by a head of government who is answerable to the legislature. This accountability and legitimacy requires that someone be chosen who has a majority support in the legislature (or, at least, not a majority opposition – a subtle but important difference). It also gives the legislature the right to vote down the head of government and their cabinet, forcing it either to resign or seek a parliamentary dissolution. The executive branch is thus said to be responsible (or answerable) to the legislature, with the head of government and cabinet in turn accepting constitutional responsibility for offering constitutional advice to the head of state.
In parliamentary constitutional monarchies, the legitimacy of the unelected head of state typically derives from the tacit approval of the people via the elected representatives. Accordingly, at the time of the Glorious Revolution, the English parliament acted of its own authority to name a new king and queen (the joint monarchs Mary II and William III); likewise, Edward VIII's abdication required the approval of each of the six independent realms of which he was monarch. In monarchies with a written constitution, the position of monarch is a creature of the constitution and could quite properly be abolished through a democratic procedure of constitutional amendment, although there are often significant procedural hurdles imposed on such a procedure (as in the Constitution of Spain).
In republics with a parliamentary system (such as India, Germany, Austria, Italy and Israel) the head of state is usually titled president and the principal functions of such presidents are mainly ceremonial and symbolic, as opposed to the presidents in a presidential or semi-presidential system.
In reality, numerous variants exist to the position of a head of state within a parliamentary system. The older the constitution, the more constitutional leeway tends to exist for a head of state to exercise greater powers over government, as many older parliamentary system constitutions in fact give heads of state powers and functions akin to presidential or semi-presidential systems, in some cases without containing reference to modern democratic principles of accountability to parliament or even to modern governmental offices. Usually, the king had the power of declaring war without previous consent of the parliament.
For example, under the 1848 constitution of the Kingdom of Italy, the Statuto Albertino—the parliamentary approval to the government appointed by the king—was customary, but not required by law. So, Italy had a de facto parliamentarian system, but a de jure "presidential" system.
Examples of heads of state in parliamentary systems using greater powers than usual, either because of ambiguous constitutions or unprecedented national emergencies, include the decision by King Leopold III of the Belgians to surrender on behalf of his state to the invading German army in 1940, against the will of his government. Judging that his responsibility to the nation by virtue of his coronation oath required him to act, he believed that his government's decision to fight rather than surrender was mistaken and would damage Belgium. (Leopold's decision proved highly controversial. After World War II, Belgium voted in a referendum to allow him to resume his monarchial powers and duties, but because of the ongoing controversy he ultimately abdicated.) The Belgian constitutional crisis in 1990, when the head of state refused to sign into law a bill permitting abortion, was resolved by the cabinet assuming the power to promulgate the law while he was treated as "unable to reign" for twenty-four hours.
These officials are excluded completely from the executive: they do not possess even theoretical executive powers or any role, even formal, within the government. Hence their states' governments are not referred to by the traditional parliamentary model head of state styles of His/Her Majesty's Government or His/Her Excellency's Government. Within this general category, variants in terms of powers and functions may exist.
The Constitution of Japan (日本国憲法,Nihonkoku-Kenpō) was drawn up under the Allied occupation that followed World War II and was intended to replace the previous militaristic and quasi-absolute monarchy system with a form of liberal democracy parliamentary system. The constitution explicitly vests all executive power in the Cabinet, who is chaired by the prime minister (articles 65 and 66) and responsible to the Diet (articles 67 and 69). The emperor is defined in the constitution as "the symbol of the State and of the unity of the people" (article 1), and is generally recognised throughout the world as the Japanese head of state. Although the emperor formally appoints the prime minister to office, article 6 of the constitution requires him to appoint the candidate "as designated by the Diet", without any right to decline appointment. He is a ceremonial figurehead with no independent discretionary powers related to the governance of Japan.
Since the passage in Sweden of the 1974 Instrument of Government, the Swedish monarch no longer has many of the standard parliamentary system head of state functions that had previously belonged to him or her, as was the case in the preceding 1809 Instrument of Government. Today, the speaker of the Riksdag appoints (following a vote in the Riksdag) the prime minister and terminates his or her commission following a vote of no confidence or voluntary resignation. Cabinet members are appointed and dismissed at the sole discretion of the prime minister. Laws and ordinances are promulgated by two Cabinet members in unison signing "On Behalf of the Government" and the government—not the monarch—is the high contracting party with respect to international treaties. The remaining official functions of the sovereign, by constitutional mandate or by unwritten convention, are to open the annual session of the Riksdag, receive foreign ambassadors and sign the letters of credence for Swedish ambassadors, chair the foreign advisory committee, preside at the special Cabinet council when a new prime minister takes office, and to be kept informed by the prime minister on matters of state.
In contrast, the only contact the president of Ireland has with the Irish government is through a formal briefing session given by the taoiseach (head of government) to the president. However, he or she has no access to documentation and all access to ministers goes through the Department of the Taoiseach. The president does, however, hold limited reserve powers, such as referring a bill to the Supreme Court to test its constitutionality, which are used under the president's discretion.
The most extreme non-executive republican head of state is the president of Israel, which holds no reserve powers whatsoever. The least ceremonial powers held by the president are to appoint the prime minister, to approve the dissolution of the Knesset made by the prime minister, and to pardon criminals or to commute their sentence.
Some parliamentary republics (like South Africa, Botswana and Myanmar) have fused the roles of the head of state with the head of government (like in a presidential system), while having the sole executive officer, often called a president, being dependent on the Parliament's confidence to rule (like in a parliamentary system). While also being the leading symbol of the nation, the president in this system acts mostly as a prime minister, since the incumbent must be a member of the legislature at the time of the election, answer question sessions in Parliament, avoid motions of no confidence, etc.
Semi-presidential systems combine features of presidential and parliamentary systems, notably (in the president-parliamentary subtype) a requirement that the government be answerable to both the president and the legislature. The constitution of the Fifth French Republic provides for a prime minister who is chosen by the president, but who nevertheless must be able to gain support in the National Assembly. Should a president be of one side of the political spectrum and the opposition be in control of the legislature, the president is usually obliged to select someone from the opposition to become prime minister, a process known as Cohabitation. President François Mitterrand, a Socialist, for example, was forced to cohabit with the neo-Gaullist (right wing) Jacques Chirac, who became his prime minister from 1986 to 1988. In the French system, in the event of cohabitation, the president is often allowed to set the policy agenda in security and foreign affairs and the prime minister runs the domestic and economic agenda.
Other countries evolve into something akin to a semi-presidential system or indeed a full presidential system. Weimar Germany, for example, in its constitution provided for a popularly elected president with theoretically dominant executive powers that were intended to be exercised only in emergencies, and a cabinet appointed by him from the Reichstag, which was expected, in normal circumstances, to be answerable to the Reichstag. Initially, the president was merely a symbolic figure with the Reichstag dominant; however, persistent political instability, in which governments often lasted only a few months, led to a change in the power structure of the republic, with the president's emergency powers called increasingly into use to prop up governments challenged by critical or even hostile Reichstag votes. By 1932, power had shifted to such an extent that the German president, Paul von Hindenburg, was able to dismiss a chancellor and select his own person for the job, even though the outgoing chancellor possessed the confidence of the Reichstag while the new chancellor did not. Subsequently, President von Hindenburg used his power to appoint Adolf Hitler as Chancellor without consulting the Reichstag.
Note: The head of state in a "presidential" system may not actually hold the title of "president" - the name of the system refers to any head of state who actually governs and is not directly dependent on the legislature to remain in office.
Some constitutions or fundamental laws provide for a head of state who is not only in theory but in practice chief executive, operating separately from, and independent from, the legislature. This system is known as a "presidential system" and sometimes called the "imperial model", because the executive officials of the government are answerable solely and exclusively to a presiding, acting head of state, and is selected by and on occasion dismissed by the head of state without reference to the legislature. It is notable that some presidential systems, while not providing for collective executive accountability to the legislature, may require legislative approval for individuals prior to their assumption of cabinet office and empower the legislature to remove a president from office (for example, in the United States of America). In this case the debate centers on confirming them into office, not removing them from office, and does not involve the power to reject or approve proposed cabinet members en bloc, so it is not accountability in the sense understood in a parliamentary system.
In the 1870s in the United States, in the aftermath of the impeachment of President Andrew Johnson and his near-removal from office, it was speculated that the United States, too, would move from a presidential system to a semi-presidential or even parliamentary one, with the speaker of the House of Representatives becoming the real center of government as a quasi-prime minister. This did not happen and the presidency, having been damaged by three late nineteenth and early twentieth century assassinations (Lincoln, Garfield and McKinley) and one impeachment (Johnson), reasserted its political dominance by the early twentieth century through such figures as Theodore Roosevelt and Woodrow Wilson.
This may even lead to an institutional variability, as in North Korea, where, after the presidency of party leader Kim Il-Sung, the office was vacant for years. The late president was granted the posthumous title (akin to some ancient Far Eastern traditions to give posthumous names and titles to royalty) of "Eternal President". All substantive power, as party leader, itself not formally created for four years, was inherited by his son Kim Jong Il. The post of president was formally replaced on 5 September 1998, for ceremonial purposes, by the office of chairman of the Presidium of the Supreme People's Assembly, while the party leader's post as chairman of the National Defense Commission was simultaneously declared "the highest post of the state", not unlike Deng Xiaoping earlier in the People's Republic of China.
While clear categories do exist, it is sometimes difficult to choose which category some individual heads of state belong to. In reality, the category to which each head of state belongs is assessed not by theory but by practice.