In most countries, a reserve power is a power that may be exercised by the head of state of a country in certain exceptional circumstances. Reserve powers should not be confused with reserved powers, a term used in the United States to denote powers that are delegated to the states, or the people therein, in accordance with the Tenth Amendment to the United States Constitution.

Constitutional monarchies

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Heads of state in countries with either an uncodified and partly unwritten constitution (such as the United Kingdom) or a wholly written constitution that consists of a text augmented by additional conventions, traditions, Letters Patent, etc. (such as the Commonwealth of Australia) generally have reserve powers. The head of state can be a monarch or the monarch's representative in a constitutional monarchy.

Typically these powers are:

1. to appoint a Prime Minister;
2. to dismiss a Prime Minister;
3. to refuse to dissolve Parliament;
4. to force a dissolution of Parliament;
5. to refuse or delay the Royal Assent to legislation. To withhold the Royal Assent amounts to a veto of a Bill. To reserve the Royal Assent in effect amounts to a decision neither to grant or refuse a dissolution, but to delay taking a decision for an undetermined period of time.
6. Royal Prerogative

There are usually strict constitutional conventions concerning when these powers may be used, and these conventions are enforced by public pressure. Using these powers in contravention of tradition would generally provoke a constitutional crisis.

Some political scientists believe that reserve powers are a good thing in that they allow for a government to handle an unforeseen crisis and that the use of convention to limit the use of reserve powers allows for more gradual and subtle constitutional evolution than is possible through formal amendment of a written constitution. Others believe that reserve powers are vestigial and potentially dangerous parts of a constitution.

Reserve powers often originate in situations in which the head of state begins with vast discretionary powers which over time become more difficult to execute in practice without provoking a constitutional crisis. As a society becomes more democratic, conventions and limitations on the power of the head of state become increasingly established and constitutional evolution occurs by establishing conventions rather than by formal amendment of the constitution. As a result, reserve powers often exist in the context of constitutional monarchies.

The Commonwealth of Nations

Within the Commonwealth realms (or dominions) until the 1920s, most reserve powers were exercised by a governor-general, on the advice of the British government, normally in the form of written instructions issued to him when he took office.

For example, the first Governor-General of the Irish Free State, Tim Healy was instructed by the British Dominions Office in 1922 to withhold the Royal Assent on any Bill passed by the two houses of Oireachtas Éireann (the Irish parliament) that attempted to change or abolish the Oath of Allegiance. However no such Bill was introduced during Healy's period in office (1922-1928). By the time the Oath was abolished, some years later, the Irish Governor-General was formally advised exclusively by the Irish government. (After a 1927 Commonwealth conference decision, the Governor-General was no longer advised by the British government, but rather, by that of each individual state).

The United Kingdom

In the United Kingdom, The Queen has numerous theoretical "personal prerogatives." In practice, however, there are no circumstances in modern British government where these could be justifiably exercised; few have been exercised in the last century. Her Majesty's personal prerogatives are:

1. The appointment of a prime minister. This was last done in 1974 when Parliament was hung and the Queen appointed Harold Wilson as prime minister. Precedent has that the monarch would send for the leader of the largest (or next-largest) party able to command the support of a majority in the House of Commons.
2. The refusal to dissolve Parliament when requested by the Prime Minister. This was last reputedly done in 1910 (but George V later changed his mind);
3. The dismissal of a Prime Minister and his Government. This was last done in Britain in 1834 by King William IV; and
4. The refusal of the Royal Assent, last exercised in 1708 by Queen Anne .

It should be noted that The Queen's personal prerogatives are quite distinct from those of her Governors-General. In 1975, the Australian Governor-General John Kerr dismissed the Government, causing a massive outcry still felt today in the republican movement. (The Queen's Private Secretary later admitted The Queen thought he had acted "prematurely").

Belgium

In 1990, when a law liberalizing Belgium's abortion laws was approved by parliament, King Baudouin refused to give his Royal Assent, only the second time in Belgium's history the monarch elected to do so. The cabinet declared him unable to reign for a day and, conforming to the Belgian Constitution's provision that, if the king is incapable of reigning, the government as a whole will fulfil the role of head of state, all members of the government signed the bill, passing it into law. The government declared that Baudouin was capable of reigning again the next day.

Republics

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Reserve powers can also be written into a republican constitution that separates the offices of Head of State and Head of Government. This was the case in Germany under the Weimar Republic, and is still the case in the French Fifth Republic and the Italian republic. Reserve powers may include, for instance, the right to issue emergency legislation or regulation bypassing the normal processes. In most states, the head of state's ability to exercise reserve powers is explicitly defined and regulated by the text of the constitution.

France

Article 16 of the Constitution of France allows the President of the Republic to exercise exceptional powers in case of a national emergency. During this time, the President may not use his prerogative to dissolve the National Assembly and call early elections. He must still consult the Prime Minister, the leaders of both houses of Parliament and the Constitutional Council.

The inspiration for this disposition in the Constitution was the institutional chaos and lack of government authority which contributed to the French debacle in the Battle of France in 1940. On a larger scale, this is consistent with a tradition of the Roman Republic (which has always been an inspiration for the successive French Republics), to give six months of dictatorial power to a citizen in case of an imminent danger of invasion.

Article 16 rule has only been exercised once, in 1961, during a crisis related to the Algerian war of independence in which Charles De Gaulle needed those emergency powers to foil a military plot to take over the government. In 1962, the Council of State ruled itself incompetent to judge measures of a legislative nature issued by the President under Article 16.

In his book, Le Coup d'État permanent (The Permanent Coup), François Mitterrand criticized Article 16 for allowing an ambitious politician the opportunity to become a dictator. However, he made no move to put away his reserve powers after he himself became President.

Germany

The Basic Law of the Federal Republic of Germany strictly limits the reserve powers available to the President to prevent the situation in which the executive could effectively rule without legislative approval, which was the case in the Weimar Republic. In particular, he cannot rule by decree and he can only dissolve the Bundestag (parliament) if the Chancellor loses a the Constitution of the Federal Republic of Germany and asks the President to do so.

The German President has exercised this right three times since the founding of the Federal Republic in 1949. President Gustav Heinemann dissolved the Bundestag at the request of Chancellor Willy Brandt in 1972 and in 1982, President Karl Carstens did so at the request of Chancellor Helmut Kohl. Both Brandt and Kohl were reelected with larger majorities. Most recently, on July 1 2005, President Horst Köhler dissolved the Bundestag at the request of Chancellor Gerhard Schröder. Schröder lost the election that followed.

The abuse of sweeping reserve powers by Adolf Hitler, given to him by the frail and easily influenced President Paul von Hindenburg, has often been cited as an important factor in the failure of the Weimar Republic and the rise of Nazism in Germany in the 1930s.

Italy

The President of the Italian Republic's powers are defined by articles 87 through 90 of the Constitution of Italy. The President:

• Can send official messages to the chambers of the Italian Parliament;
• Calls for elections;
• Has the command of the armed forces and is responsible for declaring the state of war;
• Is also the President of the High Council of Courts (Consiglio Superiore della Magistratura), the self-government body of the Italian judicial system;
• Can grant pardons and reduce sentences;
• Can call for new elections for both or only one of the chambers, except during the last six months of his term;
• Is not responsible of any actions undertaken while serving his functions, except for high treason and plotting against the Constitution.

The president can refuse to sign laws he deems clearly against the Constitution, while less obvious cases are dealt later on by the Constitutional court. This power is seldom used, because of the tensions it can foster between the ruling powers.

Trivia

• Only one Italian president has been impeached, Francesco Cossiga, but he resigned before the final vote could take place.
• Elections in Italy have always been called before their natural expiration terms by Presidents throughout the Republic's history, but most often only by short periods.
• The former Italian President, Carlo Azeglio Ciampi, was trying to pardon Adriano Sofri, convicted after a decades-long series of trials for the murder of Luigi Calabresi. Many believe Sofri to be innocent (among others, Nobel prize-winner Dario Fo campaigned for Sofri). However, Justice Minister Roberto Castelli has been recalcitrant, and has repeatedly refused to sign the pardon act.

Political science