Of the several structural challenges faced by vulnerable communities pursuing climate litigation, lack of financial resources and access to technical expertise are colossal, particularly in the Global South. In that, addressing the problem of proof in climate litigation requires securing scientific evidence of harm. While attribution science has improved over the years, it is relatively weaker in the context of Global South and vulnerable communities, including the non-human environment. Further, gathering any scientific evidence requires access to both financial resources and specialist scientific knowledge. A lack of these undermines a plaintiff’s right of access to justice, rendering them more vulnerable to climate change. The chapter presents a doctrinal response and a potential litigation strategy to address these challenges: the Indian iteration of the precautionary principle. Existing literature suggests the application of the principle to address the problem of proof. The principle allows regulatory action in supervening scientific uncertainty. However, the burden to prove ‘scientific uncertainty’ still rests on the plaintiff. Addressing this in environmental public interest litigation, the Indian Supreme Court has reversed the burden of proof. It requires the defendant to prove that the impugned activity is environmentally benign. By relieving the plaintiff from shouldering the evidentiary burden, the Indian iteration of the principle eases the aforementioned structural barriers and facilitates access to justice. Therefore, it is an instrumental litigation strategy for climate litigants from vulnerable communities across the Global South.