In the United Kingdom, the doctrine applies to all members of the government, from members of the cabinet down to Parliamentary Private Secretaries. Its inner workings are set out in the Ministerial Code. On occasion, this principle has been suspended; most notably in the 1930s when in Britain the National Government allowed its Liberal members to oppose the introduction of protective tariffs; and again when Harold Wilson allowed Cabinet members to campaign both for and against the 1975 referendum on whether the UK should remain in the European Economic Community. In 2003, Tony Blair allowed Clare Short to stay in the cabinet, despite her public opposition to the 2003 Iraq War; however, she later resigned.