Three line whip

Party whip is the name given to an official of a political party whose task is to ensure party discipline in a legislature. Whips are the party's "enforcers", they invite their MPs to attend votings and to vote according to the official party policy. The term is taken from the "whipper-in" during a hunt, who tries to prevent the hounds from wandering away from the pack (see below).

In British English The term "whip" is also used to mean:

The expression whip in its parliamentary context has its origins in hunting terminology. The Oxford English Dictionary defines the term whipper-in as, "a huntsman's assistant who keeps the hounds from straying by driving them back with the whip into the main body of the pack". According to that dictionary, the first recorded use of the term whipper-in in the parliamentary sense occurs in 1772. However, P. D. G. Thomas in House of Commons in the Eighteenth Century cites two examples of the use of the term that pre-date 1772.

It was within the context of such summonses to members out of town that the first known Parliamentary instance of the use of the term "whip" occurred. In the debate of 8 May 1769 on a petition from some Middlesex freeholders against the seating of Henry Luttrell instead of John Wilkes, Edmund Burke mentioned that the ministry had sent for their friends to the north and to Paris, "whipping them in, than which, he said, there could not be a better phrase". Although Burke's particular emphasis on the expression implied its comparative novelty, the hunting term had been used in this political context for at least a generation: on 18 November 1742 Heneage Finch remarked in a letter to Lord Malton that "the Whigs for once in their lives have whipped in better than the Tories".

In the Parliament of Australia, as well as in the parliaments of the six states and two self-governing territories, all political parties have whips to ensure party discipline and carry out a variety of other functions on behalf of the party leadership. The most important function of the whip's office is to ensure that all members and senators are present to take part in votes in the chamber (maintaining quorum and preventing censure motions). Unlike in the United Kingdom, Australian whips do not hold official office, but they are recognised for parliamentary purposes. In practice, Australian whips play a lesser role than their counterparts in the United Kingdom, as party discipline in Australia tends to be tighter.

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