The Parliament of Canada web-site has a good summary of the powers of the Senate of Canada, and includes a very interesting list of the major cases where the Senate has rejected bills passed by the Commons:
[QUOTE=THE SENATE OF CANADA - A Legislative and Historical Overview of the Senate of Canada]
With regard to the rejection of legislation sent from the House of Commons, James R. Robertson of the Library of Parliament notes the following: “Without a detailed review of the debates and records of the Canadian Senate, it is not possible to give a definitive list of bills received from the House of Commons that have been rejected by the Senate. Even MacKay and Kunz differ in their interpretation of what constitutes a rejection. It is in part, a definitional question … The Senate can reject bills outright at second or third reading, but it can also engage in other actions that amount to rejection. Similarly, Senate leaders can threaten to defeat proposed legislation, in an effort to affect or forestall government action”.
Robertson cites the following as some of the major pieces of government legislation rejected by the Senate since Confederation:
i) In 1875, the upper chamber rejected a bill for the construction of a railway from Esquimalt to Nanaimo in British Columbia on the ground it was an unwarranted public expenditure.
ii) In 1879, the Senate turned down a bill to provide for two additional judges in British Columbia on the ground that the provincial government was in the midst of an election and had, under the circumstances, no right to ask for the increase.
iii) In 1899 and 1900, the Senate rejected a bill to re-adjust representation in Ontario on the alleged ground that it was inexpedient to proceed with the bill until after the 1901 census, when re-adjustment of representation would be required under the British North America Act.
iv) In 1909, a bill which allowed appeals in claims from the Exchequer Court to provincial Supreme Courts in certain cases was rejected on the ground that it would lead to unnecessary litigation and confusion.
v) In 1913, the Senate defeated the Naval Assistance Bill and adopted the following resolution: “This House is not justified in giving its assent to the bill until it is submitted to the judgement of the country”.
vi) In 1919, a bill bringing the Biological Board of Canada under the jurisdiction of the Minister of Marine and Fisheries was thrown out on the ground that the Board should be independent and protected from political interference.
vii) In 1924, the Senate rejected seven bills sent from the Commons and drastically amended three others relating to the construction of the branch lines for the newly organized Canadian National Railway.
viii) In 1926, the Senate rejected the Old Age Pension Bill on the grounds that there was no general public demand, that the provinces had not indicated approval, and on the ground of social undesirability.
ix) From 1930 to 1940, thirteen bills from the Commons failed to pass the Senate, including one private bill relating to patents, two private members’ public bills, a bill relating to pensions for Judges, and a bill which provided for the extension of Farmers’ Creditors Arrangement Act.
x) In 1961, the Senate Banking Committee recommended that a Bill declaring vacant the post of Governor of the Bank of Canada be dropped after the former Governor, Mr. James E. Coyne, resigned.
xi) In 1961, the Senate insisted on an amendment it made to a Government Bill to amend the Customs Act.
During the 1970’s, Senate impact on Commons legislation was principally to be found in recommendations emanating from pre-study committee reports made to bills in advance of their coming before the Senate. Such pre-study of the 1975 Bankruptcy Bill led to almost 140 amendments being proposed.
During the latter 1980’s and the 1990’s, the Senate became more active in formally opposing and amending Commons legislation. Among the more controversial bills which led to confrontation between the Senate and House of Commons were the following: (i) in 1985, Bill C-11, the Borrowing Authority Bill; (ii) in 1986, Bill C-67, the “gating” amendments proposed to the Penitentiary Act; (iii) in 1987, Bill C-22, the Drug Patent Bill and Bill C-84, the Immigration Bill; (iv) in 1988, Bill C-60, the Copyright Bill, Bill C-103, the Atlantic Canada Opportunities Agency Bill and Bill C-130, the Free Trade Bill; (v) in 1989, Bill C-21, the Unemployment Insurance Act amendments; (vi) in 1990, Bill C-28, the “clawback” Income Tax Bill and Bill C-62, the Goods and Services Tax; (vii) in 1991, Bill C-43, the Abortion Bill, which was defeated at third reading; (viii) in 1996, Bill C-28, the Lester B. Pearson International Airport Bill, which was also defeated at third reading; and, (ix) in 1998, Bill C-220, the profit from authorship respecting a crime Bill, which was defeated at report stage.
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The rejection of the Naval Assistance Bill in 1913 was probably the most significant one on the list. The issue was whether Canada should contribute money to the UK government to build up the British Navy, or whether Canada should grow its own navy.
This was a matter of great public controversy, as part of the armaments race between the UK and the German Empire and the appropriate role of Canada. The issue had contributed heavily to the defeat of the Laurier government in 1911, which favoured building a Canadian Navy, and the election of the Borden government, which favoured a direct money contribution to the UK navy.
The Borden government introduced the Naval Assistance bill to provide a direct money contribution to the UK Navy. The bill passed the House of Commons, but was defeated in the Senate, where Laurier’s Liberals still had a majority.
This case, which involved the defeat of a government money bill, on a matter of great public controversy, shows that the Senate of Canada does indeed have considerable powers, if it chooses to use them.