Reservation and disallowance

Disallowance and reservation are historical constitutional powers that were instituted in several territories throughout the British Empire as a mechanism to delay or overrule legislation. Originally created to preserve the Crown's authority over colonial governments, these powers are now generally considered politically obsolete, and in many cases have been formally abolished.

In British Commonwealth and colonial territories, the legislature is typically composed of one or two legislative chambers, together with the Governor-General (or colonial Governor) acting in the name of the Sovereign. Once a bill has passed through the chambers, it is presented to the Governor-General for assent on the Sovereign's behalf. The Governor-General was formally instructed (or required by the constitution or by statute) in certain circumstances to reserve a bill for the Sovereign's "pleasure". That is, the Governor-General would neither assent nor refuse assent to the bill, but would instead refer it to the Secretary of State for the Colonies in the United Kingdom for consideration by the British government; assent, if then given, would be by the King (or Queen) in Council.

A bill assented to by a Governor-General or colonial Governor would pass into law, but might still be disallowed by the King or Queen in Council, usually within a certain timeframe after its passage. Once notice of the disallowance was communicated to the colonial authorities, the Act in question would cease to operate as law. Disallowance was not retroactive, so anything validly done under an Act's terms before its disallowance remained legal.

Sometimes a bill that had passed into law might be suspended by its own terms until the Sovereign's pleasure was made known, i.e. until the British government had advised the colonial authorities whether they were prepared to accept the legislation. Approval, if given, would again be by the King or Queen in Council.

All three methods were originally used to ensure that legislation was not repugnant to English law, did not exceed a legislature's formal competence, did not interfere with the British government's imperial or foreign policies, or even simply because the British government did not agree with the legislation.

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