1) The Secretary of State shall be under a duty to ensure that a referendum on reforming the electoral system for the House of Commons is held before 28 October 2010.
2) The referendum must offer a choice between the existing method of voting and a preferential system.
3) If the result of the referendum is in favour of changing the electoral system for the House of Commons, the Secretary of State shall be under a duty to lay implementing measures before Parliament within three months of the date of the referendum.
4) In this section:
“Implementing measures” means measures designed to and likely to implement the result of the referendum before the general election next following the referendum, and includes bills and statutory instruments.
“Preferential voting system” means a system of voting in which electors may express their support for individual candidates in order of preference and in which they are not restricted to expressing a fixed number of preferences.