Reserve powers

Reserve powers are constitutional powers a head of state may exercise independently of ministers, usually in exceptional circumstances or to preserve constitutional government.

Dismissal of a prime minister: The formal removal of a head of government from office by a head of state or other constitutional authority. A disputed dismissal tests whether the head of state can act without ministerial advice.
Constitutional convention: An established political practice that guides constitutional actors without usually being enforceable as law. Conventions often direct when formal powers must follow ministers' advice.
1975 Australian constitutional crisis: A political crisis in which Governor-General John Kerr dismissed Prime Minister Gough Whitlam and appointed Malcolm Fraser in 1975. Kerr's dismissal of Whitlam remains a defining and disputed use of reserve powers.
Ceremonial head of state: A head of state whose public duties are largely symbolic and whose formal acts ordinarily follow elected officials' advice. Reserve powers mark the limited situations in which a nominally ceremonial office may act independently.
Appointment of a prime minister: The selection and formal commissioning of a person to lead a government. Discretion may matter when no party or coalition clearly commands legislative confidence.
Royal prerogative: A body of executive powers historically held by the Crown and exercised today largely by ministers. In some systems, reserve powers are understood as a limited remnant of prerogative authority.
King–Byng affair: A 1926 Canadian constitutional dispute after Governor General Lord Byng refused Prime Minister William Lyon Mackenzie King's request to dissolve Parliament. Byng's refusal illustrates disagreement over whether a governor general may reject a prime minister's advice.
Executive power: The authority to implement laws and administer the government. Reserve powers are a narrow constitutional subset of broader executive authority.
Hung parliament: A legislature in which no party or coalition holds an overall majority. A hung parliament can force a head of state to decide whom to invite to form government.
Responsible government: A system in which the executive must retain the confidence of the elected legislature and answer to it. The requirement of legislative confidence frames when a head of state may intervene.

Linked from 7 pages