In New Zealand there is no legal requirement for the government to obtain Parliament’s consent when it deploys troops abroad. Under the Defence Act 1990 the purposes for which armed forces may be raised and maintained include the protection of the interests of New Zealand, whether in New Zealand or elsewhere, and the contribution of forces under collective security agreements and to the United Nations or in accordance with the principles of the United Nations Charter. The question of what New Zealand's interests are, and how they are best protected, is one for the government of the day.
In Australia and the United Kingdom, also, there is no legal requirement for the government to obtain parliamentary consent to troop deployments abroad, although in the United Kingdom a convention has developed that before troops are committed, the House of Commons should have the opportunity to debate the matter. In Canada Parliament must be summoned, if not in session, when Canadian forces are placed on active service, but its consent is not required for the deployment of troops abroad. In some European countries and in the United States, however, the government is required by law to gain parliament’s consent to troop deployments abroad or to notify parliament of such deployments.
The first part of this paper looks at some significant deployments of New Zealand troops overseas during the last 25 years, outlining the decision to commit troops, and associated debates and ministerial statements in Parliament. The second part of the paper summarises the legal requirements in Australia, Canada, the United Kingdom, the United States and some European countries for governments to obtain parliamentary consent to, or to notify parliament of, troop deployments abroad, and gives examples of recent practice in those countries.
This paper is concerned only with decisions to deploy troops. It does not cover declarations of war. Legal requirements regarding the type of operation that troops may engage in, e.g. that it must be authorised by the United Nations Security Council, are included only if they affect whether or not parliamentary consent to a deployment is required.