<P> Referendums are rare in Canada and only three have ever occurred at the federal level: 1898 on Prohibition, 1942 on WWII conscription, and 1992 on the Charlottetown Accord . Although the Constitution of Canada does not expressly require that amendments be approved by referendum, many argue that, in light of the precedent set by the Charlottetown Accord referendum, this may have become a constitutional convention . </P> <P> A referendum can also occur at the provincial level . The 1980 and 1995 referendums on the secession of Québec are notable cases . In conjunction with the provincial election in 2007, the province of Ontario voted on a mixed - member proportional representation electoral system and British Columbia held two consecutive referendums on BC - STV in 2005 and 2009 . In 2011 British Columbia held yet another referendum against a newly imposed HST tax . The results ended up making British Columbia the first province to overturn the harmonization of provincial and federal taxes, joining it with Alberta, which not having a provincial sales tax, has never participated in the HST . A referendum was held in the Canadian province of Prince Edward Island on November 28, 2005 to determine whether or not to adopt the Mixed Member Proportional Representation System . The referendum failed . </P> <P> There is no provision for the holding of referendums at the federal level in the United States, which the Constitution does not provide for . A constitutional amendment would be required to allow it . However, the constitutions of 24 states (principally in the West, but also in Eastern states like Massachusetts) and many local and city governments provide for referendums and citizen's initiatives . Such state - level referendums, as an example, have resulted in the limitation of property taxes as with California's Proposition 13 and Massachusetts' Proposition 21⁄2 in the late 20th century . </P> <P> However, a Constitutional Convention can be called by two - thirds of the legislatures of the States, and that Convention is empowered to propose one or more amendments to the Constitution . These amendments are then sent to the States to be approved by three - fourths of their legislatures or conventions . This route has never been taken, and there is discussion in political science circles about just how such a convention would be convened, and what kind of changes it would bring about . </P>

When does a referendum occur in the united states
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