A common line of argument for defendants in climate change litigation is that any Greenhouse Gas (“GHG”) emissions a particular defendant is responsible for is miniscule compared to the overall global output of GHG emissions. This “drop in the bucket” argument is often intertwined with issues regarding causation or redressability. For example, in one of the earliest climate change cases, a number of US States, cities, and organizations brought a lawsuit against the Environmental Protection Agency (“EPA”) for its failure to set emission standards of CO₂ and other GHG emissions for new motor vehicles. The EPA argued that the amount of GHG emissions from new motor vehicles was so insignificant that it did not contribute meaningfully to the plaintiffs’ harms, and that any relief the Court might grant would not meaningfully mitigate climate change, pointing to other nations like India and China, which were increasing their emissions: Massachusetts v. EPA, 549 U.S. 497 (2007) at 523-524.

Similar arguments continue to be made in climate change litigation worldwide and have been successful, see e.g. Juliana v. United States, 947 F. 3d 1159 (9^th Cir., 2020). These arguments are now being made in Canadian climate change litigation as well, and indeed were accepted by the majority in the Alberta Court of Appeal in Reference re Greenhouse Gas Pollution Pricing Act, 2020 ABCA 74 at para. 324. Most recently, similar arguments were made by Canada in a successful motion to strike a Charter challenge brought by youths in Federal Court, arguing there could be no meaningful remedy in the context of a justicability defence (La Rose v. Canada, 2020 FC 1008).

There is undoubtedly some attraction to these arguments. Climate change is an international problem caused by cumulative emissions that everyone emits. It requires an international solution. One court cannot solve climate change. But that misses the point. The point is not to solve climate change with one case. As Justice Stevens stated in Massachusetts, this “argument rests on the erroneous assumption that a small incremental step, because it is incremental, can never be attacked.... Yet accepting that premise would doom most challenges to regulatory action. Agencies, like legislatures, do not generally resolve massive problems in one fell regulatory swoop... They instead whittle away at them over time...” (at 524).

The same could be said for human rights litigation. Brown v. Board of Education of Topeka, 347 U.S. 483 (1954) did not end racial segregation overnight, nor did it resolve issues of racial discrimination that are still prevalent today. But these tentpole cases can serve as inspiration and hope for movements to achieve greater justice. They signal to society that things must change.

In the context of climate change, every “drop in the bucket” makes a difference. Every reduction in emissions leaves more room in the global carbon budget and more time to mitigate and adapt. As the Supreme Court of the Netherlands stated, “no reduction is negligible”: Ugrenda v. The Netherlands, 19/00135 at para. 5.7.8.

There simply is no other choice. If judges “throw up their hands,” as Justice Stanton dissenting in Juliana accuses the majority of doing, the judiciary would succumb to the fatalistic collective action problem that have paralyzed lawmakers globally for decades. Rather the judiciary must ensure that emitters of GHG emissions are responsible and accountable for their fair share of emissions. That is how we will overcome this collective action problem.