Ministerial by-election

A ministerial by-election was a by-election to fill a vacancy triggered by the appointment of the sitting member of parliament (MP) as a minister in the cabinet. The requirement for new ministers to stand for re-election was introduced in the House of Commons of Great Britain in 1707 and also featured in Westminster system parliaments modelled on it. In latter times, the by-election was usually a formality, uncontested by the opposition. In the United Kingdom, ministerial by-elections were abolished as an anachronism in 1926. The Irish Free State,Union of South Africa, and Dominion of New Zealand never had them.

Ministerial by-elections were a feature of the House of Commons of Great Britain, and its successor the House of Commons of the United Kingdom, from 1707 to 1926. Seventeenth-century English history established the doctrine of parliamentary sovereignty, in particular from interference by the monarch. In 1624, the House of Commons of England resolved that an MP could not resign his seat, and in 1680 it resolved that accepting an office of profit from the Crown would precipitate resignation from the House. Sections 24 and 25 of the Succession to the Crown Act 1707 listed ministerial offices among those considered offices of profit, while mitigating this by allowing the option of standing for re-election. A minister typically sought re-election in the same constituency he had just vacated, but occasionally contested another seat which was also vacant. In 1910 The Times newspaper noted that the relevant Act had been passed in the reign of Queen Anne "to prevent the Court from swamping the House of Commons with and pensioners", and described the process as "anomalous" and "indefensible" in the 20th century. The Reform Act 1867 made cabinet reshuffles easier by abolishing the necessity to seek re-election for an existing minister taking a new portfolio. During the First World War, temporary acts in 1915 and 1916 suspended the requirement for re-election, in order to allow the War Cabinets of the Fourth Asquith ministry and the Lloyd George ministry to be appointed quickly. The Re-Election of Ministers Act 1919 ended the requirement within nine months of a general election, and the Re-Election of Ministers Act (1919) Amendment Act 1926, introduced by the opposition as a private member's bill, ended the practice in all other cases.

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