Legislative history of limited reliability and weight

Canadian National Railway Co. v.Canada (Attorney General), 2014 SCC 40:

[47]                          This Court has observed that, while Hansard evidence is admitted as relevant to the background and purpose of the legislation, courts must remain mindful of the limited reliability and weight of such evidence (Rizzo & Rizzo Shoes Ltd. (Re), [1998] 1 S.C.R. 27, at para. 35; R. v. Morgentaler, [1993] 3 S.C.R. 463, at p. 484; Sullivan, supra, at pp. 608-14). Hansardreferences may be relied on as evidence of the background and purpose of the legislation or, in some cases, as direct evidence of purpose (Canada (Canadian Human Rights Commission) v. Canada (Attorney General), 2011 SCC 53, [2011] 3 S.C.R. 471, at para. 44, per LeBel and Cromwell JJ.). Here, Hansard is advanced as evidence of legislative intent. However, such references will not be helpful in interpreting the words of a legislative provision where the references are themselves ambiguous (Placer Dome Canada Ltd. v. Ontario (Minister of Finance), 2006 SCC 20, [2006] 1 S.C.R. 715, at para. 39, per LeBel J.). Accordingly, the evidence relied on by CN in this case does not support the argument that an implied restriction to questions of fact and policy should be read into the otherwise broad and unrestricted language in s. 40.