Canada is a constitutional monarchy, with Queen Elizabeth II (Queen of Canada) as head of state, represented by a Governor- General appointed on the recommendation of the Prime Minister. The British North America Act of 1867 set up a machinery of government that has remained basically unchanged; however, the constitution is contained in the Constitution Act of 1982, which includes the Charter of Rights and Freedoms as well as procedures for amending the constitution.
The federal parliament is bicameral. The House of Commons has 308 members directly elected in general elections which, if not called earlier, must be held on the third Monday in October in the fourth calendar year following the last election. The Senate has 105 members appointed on a regional basis by the Prime Minister, in consultation with the cabinet. The leader of the party with the most seats in the House of Commons becomes Prime Minister and appoints a cabinet which has executive power at the federal level.
In a surprise early general election in November 2000, the Liberal Party gained a decisive 173 seats, including 100 of 103 seats in the largest province of Ontario and 37 of 73 in Québec, increasing its majority by 18. Jean Chrétien continued as Prime Minister. The opposition Canadian Alliance increased its share of the popular vote – largely at the expense of the Progressive Conservative Party (PCP) – but failed to challenge the Liberal Party in the east of the country.
In December 2003, Chrétien retired and was succeeded by former Finance Minister Paul Martin, and an early general election followed in June 2004, in which the ruling Liberal Party, taking 135 seats, was ahead of the Conservatives (99 seats, the Conservative Party was formed by a merger of PCP and Canadian Alliance), but did not achieve an overall majority in the House of Commons and depended on the support of the smaller parties.
Only 17 months into its new term, in December 2005 opposition parties challenged the government on the payment by the previous Liberal government in the late 1990s of large sums of public money to advertising agencies, and, for the first time ever, carried a vote of no confidence in the government. Martin then had to call a new general election for January 2006. In this election, on a platform of tax cuts and measures to combat corruption, the Conservative Party won 124 seats, the Liberal Party 103, Bloc Québécois 51 and the New Democratic Party (NDP) 29. Conservative Party leader Stephen Harper became Prime Minister but, short of an outright majority, he was only able to introduce new legislation with support from members of other parties.
In a bid to strengthen his minority government, Harper called an election in October 2008. In the contest when turnout was 59 per cent, his Conservatives won 143 seats with 37.6 per cent of votes. Their gain was largely at the expense of the Liberals who took 77 seats; while Bloc Québécois was also down at 49 seats, NDP won 37 and independents two. Harper was returned as Prime Minister, once again in a minority government.
At an early general election, held in May 2011 after the government lost a parliamentary vote of no confidence on 25 March 2011, the ruling Conservatives secured a majority in the House of Commons with 167 of the 308 seats (39.6 per cent of votes). The NDP (102 seats and 30.6 per cent) overtook both the Liberal Party (34 seats and 18.9 per cent) and Bloc Québécois (4 seats and 6.0 per cent); the remaining seat was won by the Green Party (3.9 per cent). The new legislature included 76 women, more than ever before.