Missing the Forest for the Trees:The Supreme Court of Canada’s Formalistic Approach inthe IAA Reference a Setback for Environmental and Climate Law in Canada

Authors

Nathalie J. Chalifour, Centre for Environmental Law and Global Sustainability, University of Ottawa

Abstract

This article explores whether the Supreme Court of Canada majority’s reasons in the Reference re Impact Assessment Act missed the forest for the trees. By applying a literal interpretation to the definition of “effects within federal jurisdiction” and what the Court called the “interprovincial effects clause” in the legislation, the majority departed from decades of flexible, purposive interpretation of environmental legislation. This article highlights three interrelated critiques of this aspect of the decision. First, it unpacks the way in which the majority’s reasons run contrary to the Supreme Court’s consistent approach to interpreting environmental legislation in previous decisions, inviting readers to reflect upon whether this shift in statutory interpretation undermines the validity of most environmental legislation which is drafted in a similarly broad way. Second, the article critically examines the majority’s conclusion that the “interprovincial effects” clause was ultra vires, inviting consideration of whether the decision creates a constitutional gap for evaluating the effects of transboundary air pollution in impact assessments. Third, the article responds to the majority’s admonition that the government had not attempted to apply the clarified national concern test from the GGPPA References to the interprovincial effects clause, analysing what this might have yielded. The decision has important implications for understanding the scope of jurisdiction over GHG emissions in our federation. Whereas the GGPPA References clarified that both orders of government have jurisdiction over different aspects of GHG emissions, the IAA Reference creates uncertainty about Parliament’s jurisdiction to consider transboundary air pollution — an aspect that must be federal — in assessments. The decision also reveals a striking shift in tone in the Supreme Court’s approach to interpreting environmental law, raising concerns about the future of environmental and climate federalism. The implications are significant given the increasingly urgent need for all governments to do their part in mitigating the climate emergency.

Citation Information

Chalifour, Nathalie J.. "Missing the Forest for the Trees:The Supreme Court of Canada’s Formalistic Approach inthe IAA Reference a Setback for Environmental and Climate Law in Canada." The Supreme Court Law Review, Third Series: Osgoode's Annual Constitutional Cases Conference 5. (2026).
DOI: https://doi.org/10.60082/2563-8505.1001
https://digitalcommons.osgoode.yorku.ca/sclr-third-series/vol5/iss1/2

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This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

References

1 See e.g., R. v. Crown Zellerbach Canada Ltd., [1988] S.C.J. No. 23, [1988] 1 S.C.R. 401 (S.C.C.); Friends of the Oldman River Society v. Canada (Minister of Transport), [1992] S.C.J. No. 1, [1992] 1 S.C.R. 3 (S.C.C.); R. v. Hydro-Québec, [1997] S.C.J. No. 76, [1997]

3 S.C.R. 213 (S.C.C.) [hereinafter "Hydro-Québec"].

2 See e.g., References re Greenhouse Gas Pollution Pricing Act, [2021] S.C.J. No. 11, 2021 SCC 11 (S.C.C.) [hereinafter "GGPPA References"]; Syncrude Canada Ltd. v. Canada (Attorney General), [2016] F.C.J. No. 572, 2016 FCA 160 (F.C.A.) (challenging federal regulations requiring a minimum percentage of renewable content in diesel fuels). Alberta Premier Danielle Smith has threatened to challenge future climate regulations proposed by the federal government. See online: https://www.cbc.ca/news/politics/climate-electricitydanielle-smith-sovereignty-1.7041515.

3 Impact Assessment Act, S.C. 2019, c. 28 [hereinafter the "IAA"].

4 [2023] S.C.J. No. 23, 2023 SCC 23 (S.C.C.) [hereinafter "IAA Reference"].

5 The decision held that the portion of the IAA that deals with projects carried out or financed by federal authorities on federal lands or outside the country (s. 81-91) was intra vires. This article focuses on the rest of the IAA which deals with "designated projects". See IAA Reference, at paras. 5-6 (S.C.C.). For a thorough and thoughtful discussion of the decision and its implications, see Martin Olszynski, Nigel Bankes & David Wright, "Wait, What!? What the Supreme Court Actually Said in the IAA Reference" (October 16, 2023), online (blog): http://ablawg.ca/wp-content/uploads/2023/10/Blog_MO_NB_DW_IAA_Reference.pdf; Anna Johnston, "Two wins, a loss, and a question mark: What the Impact Assessment Act reference case means for the environment" (October 18, 2023), online (blog): https://www.wcel.org/blog/two-wins-loss-and-question-mark-what-impact-assessment-actreference-case-means-environment. See also Robert Hamilton, "The IAA Reference: A Missed Opportunity for Guidance on Important Issues Pertaining to Indigenous Peoples" (October 25, 2023), online (blog): http://ablawg.ca/wp-content/uploads/2023/10/Blog_RH_IAA_Ref.pdf (discussing a missed opportunity for the judiciary to provide clarity on important issues relating to federal jurisdiction and Indigenous lands and peoples).

6 Office of the Auditor General of Canada, Reports of the Commission of the Environment and Sustainable Development to the Parliament of Canada, "Canadian Net-Zero Emissions Accountability Act - 2030 Emissions Reduction Plan: Report 6" (2023), at iii, see online: https://www.oag-bvg.gc.ca/internet/docs/parl_cesd_202311_06_e.pdf.

7 Government of Canada, Regulatory Framework for an Oil and Gas Sector Greenhouse Gas Emissions Cap (2023), see online: https://www.canada.ca/en/services/environment/weather/climatechange/climate-plan/oil-gas-emissions-cap/regulatory-framework.html.

8 As discussed later in the article, the Chief Justice noted that Canada made no attempt to do to this. IAA Reference, at para. 187 (S.C.C.). See also The Energy Mix, "Ottawa Cedes Authority over GHG Emissions in Impact Assessment Act Amendments" (May 6, 2024), online: https://www.theenergymix.com/ottawa-cedes-authority-over-ghg-emissions-in-impactassessment-act-amendments/; David V. Wright, "Constitutional Caution, Correction, and Abdication: The Proposed Amendments to the Impact Assessment Act" (May 10, 2024), online (blog): http://ablawg.ca/wp-content/uploads/2024/05/Blog_DW_IAA_Amendments.pdf.

9 See Government of Canada, "Amended Impact Assessment Act now in force" (June 21, 2024), online: https://www.canada.ca/en/impact-assessment-agency/news/media-room/amended-impact-assessment-act-now-in-force.html. The precise language is "a nonnegligible adverse change to the marine environment that is caused by pollution - that is caused by pollution - to boundary waters or international waters . . ." and boundary.

10 See e.g., Luc Rinaldi, "The Unsteady Reign of Danielle Smith", MacLean's Magazine (September 14, 2023), online: https://macleans.ca/politics/unsteady-reign-danielle-smith/.

11 IAA Reference, at para. 189 (S.C.C.).

12 GGPPA References, at para. 126 (S.C.C.). For discussion of the double aspect doctrine in the context of the national concern doctrine, see Nathalie J. Chalifour, Peter Oliver & Taylor Wormington, "Clarifying the Matter: Modernizing Peace, Order, and Good Government in the Greenhouse Gas Pollution Pricing Act Appeals" (2020) 40 N.J.C.L. 153; Andrew Leach & Eric M. Adams, "Seeing Double: Peace, Order, and Good Government, and the Impact of Federal Greenhouse Gas Emissions Legislation on Provincial Jurisdiction" (2020) 29 Const. Forum Const. 1. https://doi.org/10.21991/cf29392

13 See Martha Jackman, "Wizened Stump or Living Tree? Section 7 Principles of Fundamental Justice" in Howard Kislowicz, Kerri Froc & Richard Moon, eds., The Surprising Constitution (Vancouver: UBC Press, 2024) at 260-285 https://doi.org/10.59962/9780774870061-013; See also Larissa Parker, "Let our Living Tree Grow: Beyond Non-Justiciability for the Adjudication of Wicken Problems" (2023) 81:1 U.T. Fac. L. Rev.

14 See generally, Meinhard Doelle & A. John Sinclair, The Next Generation of Impact Assessment: A Critical Review of the Canadian Impact Assessment Act (Toronto: Irwin Law, 2021); Robert B. Gibson, Sustainability Assessment: Applications and Opportunities (Oxon: Earthscan/Routledge, 2017).

15 See Neil Craik, "The Duty to Cooperate in the Customary Law of Environmental Impact Assessment" (2020) 69:1 Inti. & C.L.Q. 239. See also Jocelyn Stacey, "The Deliberative Dimensions of Modern Environmental Assessment Law" (2020) 43:2 Dal. L.J. 865. https://doi.org/10.1017/S0020589319000459

16 See International Tribunal for the Law of the Sea, Request for an Advisory Opinion Submitted by the Commission of Small Island States on Climate Change and International Law: Advisory Opinion (May 21, 2024), https://www.itlos.org/fileadmin/itlos/documents/cases/31/Advisory_Opinion/C31_Adv_Op_21.05.2024_orig.pdf.

17 The evolution of environmental assessment in Canada has a deep and complex political dimension. The major changes to federal assessment introduced by the Harper administration (reflected in the third iteration of federal assessment law, CEAA 2012) sparked concern among environmental groups and among Indigenous peoples. The major changes were one of the impetus for the Idle No More movement and unsuccessful constitutional litigation by First Nations. See, e.g., Mikisew Cree First Nation v. Canada (Governor General in Council), [2018] S.C.J. No. 40, 2018 SCC 40 (S.C.C.). See generally Grace Li Xiu Woo, "Decolonization and Canada's 'Idle No More' Movement" (2013) 4:2 Arctic Rev. on Law & Politics 181; For more on the political dimensions, see Meinhard Doelle & A. John Sinclair, The Next Generation of Impact Assessment: A Critical Review of the Canadian Impact Assessment Act (Toronto: Irwin Law, 2021).

18 See e.g., IAA, s. 22(1). See Robert Gibson, Sustainable Assessment: Applications and Opportunities (Oxon: Routledge, 2017), for an exploration of sustainable assessment as an evolution from environmental impact assessment.

19 Government of Canada, "Policy Context: Indigenous Participation in Impact Assessment" (2024), see online: https://www.canada.ca/en/impact-assessment-agency/services/policy-guidance/practitioners-guide-impact-assessment-act/policy-indigenous-participation-ia.html. See Robert Hamilton, "The IAA Reference: A Missed Opportunity for Guidance on Important Issues Pertaining to Indigenous Peoples" (October 25, 2023), online (blog): http://ablawg.ca/wp-content/uploads/2023/10/Blog_RH_IAA_Ref.pdf for a critique of the IAA in relation to Indigenous peoples and lands.

20 The IAA includes provisions related to strategic environmental assessments in s. 95-103. The federal government published a strategic assessment of climate change in 2019 that guides project proponents on the kind of climate-related information they must submit during the assessment process, including a credible plan for achieving net-zero emissions by 2050. See Government of Canada, Strategic Assessment of Climate Change Revised, October 2020, https://www.canada.ca/en/services/environment/conservation/assessments/strategicassessments/climate-change.html. The IAA Reference did not comment on the strategic assessment process.

21 GGPPA References, at para. 2 (S.C.C.).

22 Expert Panel Report, "Building Common Ground: A New Vision for Impact Assessment in Canada" (2017), see online: https://www.canada.ca/en/services/environment/conservation/assessments/environmental-reviews/environmental-assessment-processes/buildingcommon-ground.html.

23 Then Alberta Premier called Bill C-69 (which later became the Impact Assessment Act) the "No More Pipelines Act" and promised to challenge its constitutionality as soon as it became law. See Sarah Cox, "Senate changes to environmental assessment bill are worse than Harper-era legislation: experts", The Narwhal (June 7, 2019), online: https://thenarwhal.ca/senate-changes-to-environmental-assessment-bill-are-worse-than-harper-era-legislationexperts/.

24 Since the IAA was amended in 2024 following the Supreme Court of Canada's decision, I will refer to the 2019 IAA and the 2024 IAA to distinguish between the pre- and post-amendment version of the law.

25 See e.g., the IAA, s. 22(1)(i) & 63(e).

26 IAA Reference, at paras. 34-37 (S.C.C.).

27 For an evaluation of the IAA, see Anna Johnston et al, "Is Canada's Impact Assessment Act working?" (2021), see online: https://www.wcel.org/sites/default/files/publications/2021-impact-assessment-act-report-en-web.pdf.

28 IAA Reference, at paras. 38-41 (S.C.C.).

29 IAA Reference, at paras. 42-45 (S.C.C.).

30 IAA Reference, at para. 46 (S.C.C.). Note that the IAA amendments made post-decision limited the factors to be considered in the decision-making stage to three.

31 IAA, s. 7(1).

32 As noted earlier, the Court held that s. 81-91 of the IAA were intra vires. When discussing the decision, I am referring to the designated projects portion of the IAA.

33 IAA Reference, at paras. 140-178 (S.C.C.). The portion of the IAA focused on physical activities on federal lands or outside Canada (s. 81-91) were held to be intra vires. See IAA Reference, at paras. 47-49 & 207-211 (S.C.C.).

34 IAA Reference, at para. 178 (S.C.C.).

35 IAA Reference, at para. 179 (S.C.C.).

36 IAA Reference, at para. 182 (S.C.C.).

37 IAA Reference, at paras. 217-361 (S.C.C.).

38 IAA Reference, at paras. 94-96 (S.C.C.).

39 IAA, s. 2 (emphasis added).

40 IAA Reference, at para. 183 (S.C.C.).

41 IAA, s. 2; IAA Reference, at para. 183 (S.C.C.).

42 IAA Reference, at para. 183 (S.C.C.).

43 See Canadian Environmental Protection Act, S.C. 1999, c. 33, s. 3(1) the Alberta Environmental Protection and Enhancement Act, R.S.A. 2000, c. C-12, s. 1(t). The Ontario Environmental Protection Act defines the natural environment as "the air, land and water, or any combination or part thereof, of the Province of Ontario" (Ontario Environmental Protection Act, R.S.O. 1990, c. E. 19, s 1(1)).

44 IAA Reference, at para. 181 (S.C.C.).

45 IAA Reference, at para. 182 (S.C.C.).

46 IAA Reference, at para. 183 (S.C.C.).

47 IAA Reference, at para. 184 (S.C.C.).

48 IAA Reference, at para. 184 (S.C.C.).

49 IAA Reference, at para. 184 (S.C.C.).

50 IAA Reference, at paras. 195-196 (S.C.C.).

51 IAA Reference, at para. 184 (S.C.C.).

52 IAA Reference, at para. 186 (S.C.C.), citing GGPPA References, at para. 199 (S.C.C.).

53 IAA Reference, at para. 188 (S.C.C.).

54 IAA Reference, at para. 188 (S.C.C.).

55 See online: https://ecojustice.ca/news/ecojustice-in-court-to-fight-coalspur-minesattempt-to-expand-vista-thermal-coal-mine-without-federal-impact-assessment/ (emphasis added).

56 Canada's total annual GHG emissions in 2022 were 708 MT. See Government of Canada, Greenhouse Gas Emissions, online: https://canada.ca/en/environment-climatechange/services/environmental-indicators/greenhouse-gas-emissions.html.

57 On the presumption, see generally Paul Daly, "Constitutionally Conforming Interpretation in Canada" (January 21, 2022), in Matthias Klatt, ed., Constitutionally Conforming Interpretation: Volume I (Oxford: Hart Publishing, 2022), Ottawa Faculty of Law Working Paper No. 2022-05, see online: https://ssrn.com/abstract=4014736 or http://dx.doi.org/10.2139/ssrn.4014736>.

58 IAA Reference, at para. 234 (S.C.C.).

59 IAA Reference, at para. 224 (S.C.C.).

60 Affidavit of Daniel Cheater, affirmed June 9, 2020, Tab A (Appeal Record of the Attorney General of Canada, Vol. 11, Tab 17).

61 See, e.g., Ontario v. Canadian Pacific Ltd., [1995] S.C.J. No. 62, [1995] 2 S.C.R. 1031, at para. 55 (S.C.C.) [hereinafter "Canadian Pacific"]; Hydro-Québec, at para. 127 (S.C.C.); 114957 Canada Ltée (Spraytech, Société d'arrosage) v. Hudson (Town), [2001] S.C.J. No. 42, 2001 SCC 40, at para. 1 (S.C.C.); Friends of the Oldman River Society v. Canada (Minister of Transport), [1992] S.C.J. No. 1, [1992] 1 S.C.R. 3, at 16-17 (S.C.C.).

62 See e.g., Canadian Pacific (S.C.C.).

63 [2013]S.C.J. No. 52, 2013 SCC 52 (S.C.C.). https://doi.org/10.1002/wilm.10184

64 Castonguay Blasting Ltd. v. Ontario (Environment), [2013] S.C.J. No. 52, 2013 SCC 52, at para. 9 (S.C.C.).

65 Canadian Pacific, at paras. 43-44 (S.C.C.).

66 Hydro-Québec, at paras. 107 & 133 (S.C.C.).

67 See Hydro-Québec, at para. 147 (S.C.C.) (summarizing the procedure) and IAA Reference, at para. 46 (S.C.C.) (summarizing the decision-making stage in the IAA).

68 IAA Reference, at para. 74 (S.C.C.), citing the dissent in Hydro-Québec, at para. 73 (S.C.C.). Counsel for Alberta cited this paragraph in their Factum, at para. 58. The Attorney General of Alberta, Factum of the Respondent, Reference re Impact Assessment Act (S.C.C. Court file: 40195) November 23, 2022.

69 Hydro-Québec, at paras. 147-148 (S.C.C.).

70 [1979] 2 S.C.R. 618, at 641 (S.C.C.), citing Reference re Farm Products Marketing Act (Ontario), [1957] S.C.R. 198, at 255 (S.C.C.).

71 Canadian Broadcasting Corp. v. Québec (Police Commission), [1979] 2 S.C.R. 618, at 641 (S.C.C.), citing Reference re Farm Products Marketing Act (Ontario), [1957] S.C.R. 198, at 255 (S.C.C.). See also Murray-Hall v. Québec (Attorney General), [2023] S.C.J. No. 10, 2023 SCC 10, at para. 79 (S.C.C.)

Desgagnés Transport Inc. v. Wärtsilä Canada Inc., [2019] S.C.J. No. 58, 2019 SCC 58, at para. 28 (S.C.C.).

72 Reference re Farm Products Marketing Act (Ontario), [1957] S.C.R. 198, at 255 (S.C.C.).

73 See generally Martin Olszynski, "Ancient Maxim, Modern Problems: De Minimis, Cumulative Environmental Effects and Risk-Based Regulation" (2015) 40:2 Queen's L.J. 705 (distinguishing between the well-settled role of the maxim in statutory interpretation and its less settled role as a defence, and exploring the maxim's role in managing cumulative effects in regulation).

74 Castonguay Blasting Ltd. v. Ontario (Environment), [2013] S.C.J. No. 52, 2013 SCC 52, at para. 18 (S.C.C.).

75 See e.g., Canadian Environmental Protection Act, S.C. 1999, c. 33, s. 3(1) and Alberta Environmental Protection and Enhancement Act, R.S.A. 2000, c. C-12, s. 1(t) (the exact same definition). The Ontario Environmental Protection Act defines the natural environment as "the air, land and water, or any combination or part thereof, of the Province of Ontario" Ontario Environmental Protection Act, R.S.O. 1990, c. E. 19, s. 1(1). See also IAA, s. 2 and accompanying text.

76 For an excellent discussion of this issue of literal interpretation, see Martin Olszynski, "Triviality and Significance of Federal Environmental Effects after Reference re Impact Assessment Act" (January 15, 2024), online (blog): http://ablawg.ca/wp-content/uploads/2024/01/Blog_MO_Triviality_Federal_IAA.pdf.

77 Castonguay Blasting Ltd. v. Ontario (Environment), [2013] S.C.J. No. 52, 2013 SCC 52 (S.C.C.).

78 The Government of Canada led evidence to this effect, demonstrating practice of the Canadian Environmental Assessment Agency to target only significant impacts. Affidavit of Daniel Cheater, affirmed June 9, 2020, Tab A (Appeal Record of the Attorney General of Canada, Vol. 11, Tab 17).

79 IAA Reference, at para. 160 (S.C.C.).

80 See IAA Reference, at para. 35 (S.C.C.) (where the court explains that the designated project list focuses on activities that have the greatest potential to have adverse effects on areas of federal jurisdiction).

81 IAA Reference, at para. 1 (S.C.C.).

82 IAA Reference, at paras. 183-184 (S.C.C.).

83 This does not account for the jurisdictional space of Indigenous legal orders that preceded colonialization and continue to exist in parallel to the settler Constitution. For more on Indigenous legal orders in a constitutional context, see John Borrows, Canada's Indigenous Constitution (Toronto: University of Toronto Press, 2010); See also Val Napoleon, "Thinking about Indigenous Legal Orders", in R. Provost & Colleen Sheppard, eds., Dialogues on Human Rights and Legal Pluralism, at 229-245.

84 [2004] S.C.J. No. 75, 2004 SCC 79, at para. 34 (S.C.C.). See also Reference re Securities Act, [2011] S.C.J. No. 66, 2011 SCC 66 (S.C.C.); Reference re Firearms Act (Canada), [2000] S.C.J. No. 31, 2000 SCC 31 (S.C.C.). https://doi.org/10.1177/0967010600031003010

85 Reference re Securities Act, [2011] S.C.J. No. 66, 2011 SCC 66, at paras. 81-83 (S.C.C.). https://doi.org/10.1061/ciegag.0000341

86 IAA Reference, at para. 350 (S.C.C.), citing Reference re Seabed and subsoil of the continental shelf offshore Newfoundland, [1984] S.C.J. No. 7, [1984] 1 S.C.R. 86, at 128-129 (S.C.C.).

87 IAA Reference, at para. 350 (S.C.C.), citing Interprovincial Co-Operatives Ltd. v. Dryden Chemicals Ltd., [1976] 1 S.C.R. 477 (S.C.C.).

88 IAA Reference, at para. 185 (S.C.C.), citing Interprovincial Co-Operatives Ltd. v. Dryden Chemicals Ltd., [1976] 1 S.C.R. 477, at 514 (S.C.C.).

89 IAA Reference, at para. 186 (S.C.C.).

90 GGPPA References, at para. 199 (S.C.C.) (the examples include provincial legislation with respect to roads, building codes, public transit and home heating).

91 See, e.g., Syncrude Canada Ltd. v. Canada (Attorney General), [2016] F.C.J. No. 572, 2016 FCA 160 (F.C.A.) (upholding renewable energy regulations under the Canadian Environmental Protection Act).

92 IAA Reference, at para. 119 (S.C.C.).

93 IAA Reference, at para. 119 (S.C.C.); Desgagnés Transport Inc. v. Wärtsilä Canada Inc., [2019] S.C.J. No. 58, 2019 SCC 58, at para. 83 (S.C.C.); Multiple Access Ltd. v. McCutcheon, [1982] S.C.J. No. 66, [1982] 2 S.C.R. 161, at 180-181 (S.C.C.); Canadian Western Bank v. Alberta, [2007] S.C.J. No. 22, 2007 SCC 22, at paras. 36 & 42 (S.C.C.).

94 IAA Reference, at para. 184 (S.C.C.).

95 IAA Reference, at para. 184 (S.C.C.).

96 IAA Reference, at para. 187 (S.C.C.).

97 Impact Assessment Act (S.C. 2019, c. 28, s. 1), section 2, amended June 19, 2024. See Impact Assessment Agency of Canada, The amended Impact Assessment Act Factsheet, online: https://www.canada.ca/content/dam/iaac-acei/documents/acts-regulations/Amended_Impact_Assessment_Act.pdf.

98 See, e.g., R. (Finch) v. Surrey County Council and others, [2024] UKSC 20 (U.K. Supreme Court).

99 IAA Reference, at para. 189 (S.C.C.).

100 GGPPA References, at para. 133 (S.C.C.).

101 GGPPA References, at paras. 134, 136 & 141 (S.C.C.).

102 R. v. Comeau, [2018] S.C.J. No. 15, 2018 SCC 15, at para. 52 (S.C.C.); GGPPA References, at para. 137 (S.C.C.).

103 GGPPA References, at para. 140 (S.C.C.).

104 IAA Reference, at para. 145 (S.C.C.).

105 GGPPA References, at para. 148 (S.C.C.).

106 GGPPA References, at para. 151 (S.C.C.). For a thoughtful argument about inverted subsidiarity (where there is a unique role for Parliament in matters best dealt with at a national level), see Jean Leclair, "'Tis a rock - a crag - a cape? A cape? Say rather a peninsula!' The Supreme Court of Canada's Revisitation of the National Concern Doctrine" (2023) 108 S.C.L.R. (2nd) 3. https://doi.org/10.60082/2563-8505.1432

107 GGPPA References, at para. 152 (S.C.C.).

108 GGPPA References, at para. 153 (S.C.C.).

109 GGPPA References, at para. 156 (S.C.C.).

110 GGPPA References, at para. 187 (S.C.C.).

111 GGPPA References, at para. 155 (S.C.C.).

112 GGPPA References, at para. 155 (S.C.C.).

113 GGPPA References, at para. 160 (S.C.C.).

114 GGPPA References, at para. 161 (S.C.C.).

115 GGPPA References, at para. 206 (S.C.C.).

116 IAA Reference, at para. 109 (S.C.C.).

117 The majority's conclusion that the decision-making stage allowed Parliament to concluding that factoring in non-federal adverse effects at the public interest stage transformed the decision to one that was about the project as a whole versus the federal effects of the project. The majority's reasons suggest it is acceptable to consider positive non-federal impacts (such as economic benefits like jobs), which may justify approving a project even if it has significant adverse effects on federal jurisdiction, such as fish habitat, but that it is not acceptable to consider negative non-federal impacts (such as economic risks). See Anna Johnston, Two wins, a loss, and a question mark: What the Impact Assessment reference case means for the environment (October 18, 2023), online: https://www.wcel.org/blog/two-winsloss-and-question-mark-what-impact-assessment-act-reference-case-means-environment.

118 GGPPA References, at paras. 2, 167 & 171 (S.C.C.).

119 GGPPA References, at para. 167 (S.C.C.).

120 GGPPA References, at para. 171 (S.C.C.).

121 GGPPA References, at para. 194 (S.C.C.).

122 GGPPA References, at para. 171 (S.C.C.).

123 [1993] S.C.J. No. 99, [1993] 3 S.C.R. 327, at 340, 352 & 379-380 (S.C.C.), cited in GGPPA References, at para. 107 (S.C.C.).

124 IAA Reference, at para. 145 (S.C.C.).

125 Section 4 of the Canadian Net-Zero Emissions Accountability Act, S.C. 2021, c. 22 legislates the 2050 net-zero goal. https://doi.org/10.1016/j.focat.2021.11.018

126 GGPPA References, at para. 195 (S.C.C.). See Hydro-Québec, at para. 76 (S.C.C.).

127 Interprovincial Co-Operatives Ltd. v. Dryden Chemicals Ltd., [1976] 1 S.C.R. 477, at 514 (S.C.C.).

128 The SCC illustrated this point in the context of carbon pricing in the GGPPA References, at para. 184 (S.C.C.), noting that the decreases in emissions in some provinces were offset by increases in other provinces.

129 See Reference re Pan-Canadian Securities Regulation, [2018] S.C.J. No. 48, 2018 SCC 48, at para. 113 (S.C.C.). See also GGPPA References, at para. 182 (S.C.C.). 130 See, e.g., the evidence summarized by the SCC in the GGPPA References showing how growth of emissions in Alberta and Saskatchewan offset decreases in emissions in other provinces. GGPPA References, at para. 184 (S.C.C.).

131 See e.g., Hoge Raad, The Hague, December 20, 2019, Netherlands v. Urgenda (January 13, 2020), ECLI:NL:HR:2019:2007 (Supreme Court of the Netherlands) (the first case where the human rights dimensions of climate change were recognized by a court) Notre Affaire à Tous and Others v. France, Bundesverfassungsgericht (Federal Constitutional Court), Karlsruhe, February 6, 2020, Neubauer v. Germany, 00362/19/R/H (Germany) (constitutional complaint) (holding the German government responsible for mitigating climate change). For a review of climate litigation, see UNEP & Columbia Law School, Global Climate Litigation Report, 2023 Status Review, online: https://wedocs.unep.org/bitstream/handle/20.500.11822/43008/global_climate_litigation_report_2023.pdf?sequence=3.

132 GGPPA References, at para. 195 (S.C.C.).

133 Nathalie J. Chalifour, "Jurisdictional Wrangling over Climate Policy in the Canadian Federation: Key Issues in the Provincial Constitutional Challenges to Parliament's Greenhouse Gas Pollution Pricing Act" (2020) 50:2 Ottawa L. Rev. 197, at 237-243

Nathalie J. Chalifour, "Canadian Climate Federalism: Parliament's Ample Constitutional Authority to Legislate GHG Emissions through Regulations, a National Cap and Trade Program or a National Carbon Tax" (2016) 36 N.J.C.L. 331, at 355-360. https://doi.org/10.2139/ssrn.2775370

134 GGPPA References, at paras. 399-403 (S.C.C.); GGPPA References, (Factum of the Intervenor, David Suzuki Foundation); GGPPA References, (Factum of the Intervenor, Friends of the Earth Canada and National Association of Women and the Law, at paras. 16-18).

135 See David V. Wright, "Constitutional Caution, Correction, and Abdication: The Proposed Amendments to the Impact Assessment Act" (May 10, 2024), online: http://ablawg.ca/wp-content/uploads/2024/05/Blog_DW_IAA_Amendments.pdf; Meinhard Doelle, "Integrating Climate Change into Environmental Impact Assessments: Key Design Elements" (October 26, 2018), online: https://ssrn.com/abstract=3273499.

136 See e.g., Canadian Net Zero Emissions Accountability Act, S.C. 2021, c. 22 (which, inter alia, establishes national targets and reporting mechanisms)

Clean Fuel Regulations, S.O.R./2022-140, under the Canadian Environmental Protection Act, 1999, S.C. 1999, c. 33.

137 See Eric M. Adams, "Touch of Evil: Disagreements at the Heart of the Criminal Law Power" (2022) 104 S.C.L.R. (2d) 67. https://doi.org/10.60082/2563-8505.1426

138 Responsible Plastic Use Coalition v. Canada (Environment and Climate Change), [2023] F.C.J. No. 1955, 2023 FC 1511 (F.C.).

139 Intergovernmental Panel on Climate Change, Climate Change 2023: Synthesis Report, Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, Core Writing Team et al, eds. (Geneva, 2023).

140 During the same week as the Constitutional Conferences case unfolded, the European Court of Human Rights held the Swiss government accountable for failing to meet its targets in a groundbreaking case that joins dozens of others around the world. See United Nations Environment Programme, "Global Climate Litigation Report: 2023 Status Review" (July 27, 2023), online: https://wedocs.unep.org/bitstream/handle/20.500.11822/43008/global_climate_litigation_report_2023.pdf?sequence=3; see also Joana Setzer & Catherine Higham, "Global trends in climate change litigation: 2024 snapshot" (June 2024), online: https://www.lse.ac.uk/granthaminstitute/wp-content/uploads/2024/06/Global-trends-in-climate-change-litigation-2024-snapshot.pdf.

141 See e.g., Mathur (Litigation guardian of) v. Ontario, [2023] O.J. No. 1691, 2023 ONSC 2316 (Ont. S.C.J.); La Rose v. Canada, [2023] F.C.J. No. 2260, 2023 FCA 241 (F.C.A.); Dykstra et al v. Saskatchewan Power Corporation (pending action).