Reserve power

In a parliamentary or semi-presidential system of government, a reserve power is a power that may be exercised by the head of state without the approval of another branch of the government. Unlike in a presidential system of government, the head of state is generally constrained by the cabinet or the legislature in a parliamentary system, and most reserve powers are usable only in certain exceptional circumstances. In some countries, reserve powers go by another name; for instance, the reserve powers of the President of Ireland are called discretionary powers.

In monarchies with either an uncodified or partly unwritten constitution (such as the United Kingdom or Canada) or a wholly written constitution that consists of a text augmented by additional conventions, traditions, letters patent, etc. (such as Australia), the monarch generally possesses reserve powers.

Typically these powers are: to grant pardon; to dismiss a prime minister; to refuse to dissolve parliament; and to refuse or delay royal assent to legislation (to withhold royal assent amounts to a veto of a bill, while to reserve royal assent in effect amounts to a decision to neither grant nor refuse assent, but to delay taking a decision for an undetermined period). 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.

Most constitutional monarchies employ a system that includes the principle of responsible government. In such an order, the reserve powers are thought to be the means by which the monarch and his or her viceregal representatives can legitimately exist as "constitutional guardians" or "umpires", tasked with guaranteeing that Cabinet and parliament adhere to the fundamental constitutional principles of the rule of law and responsible government itself. Some constitutional scholars, such as George Winterton, have stated that reserve powers are a good thing in that they allow for a head of state 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, such as Herbert Evatt, believe or believed that reserve powers are vestigial and potentially open to abuse. Evatt felt that the reserve powers could be codified and still serve their intended function in a responsible government system, as they do in Sweden, Ireland, and Japan.

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