General Strategies to Use in Climate Litigation

Use Scientific Evidence
Scientific evidence is the basis for many arguments made in climate litigation cases. Climate science is needed to establish the causes and impacts of climate change. A branch of climate science known as Attribution Science is needed to tie a company or country to a specific percentage of greenhouse gas emissions, which is often necessary to explain the company or country's specific role in causing the climate crisis.

Climate science is often featured prominently in the courtroom of climate litigation cases. In Oakland v. BP, the judge requested a full-day tutorial on climate change and climate science. In Juliana v. United States, climatologist James Hansen participated as a plaintiff on behalf of future generations.

Resources: The Intergovernmental Panel on Climate Change (IPCC) is viewed as an authoritative source for the latest consensus on climate science and is often cited in climate litigation.

Attribute Emissions to Emitters
One strategy is to calculate the percentage of historical greenhouse gas emissions produced by a company or country, and then suing that entity for a percentage of adaptation costs that corresponds with their contribution to climate change. For example, in Lliuya v. RWE, it was determined that RWE was responsible for 0.47% of historical greenhouse gas emissions, so the plaintiffs sought damages equal to 0.47% of the cost of adapting to flood risk to their community.

Resources: Climate Accountability Institute, Union of Concerned Scientists

Overcoming the "Drop in the Bucket" argument
A common argument used to oppose climate change liability is that the polluter or country represents a small percentage of global emissions and that any action by the court won't significantly impact the trajectory of climate change.

This argument was rejected by the appeals court in Lliuya v. RWE. It is also worth reading the powerful dissent in the Juliana case by Judge Josephine Staton, who wrote: "'The majority portrays any relief we can offer as just a drop in the bucket. In a previous generation, perhaps that characterization would carry the day and we would hold ourselves impotent to address plaintiffs’ injuries. But we are perilously close to an overflowing bucket. These final drops matter. A lot.'"

Use Visuals
People are more responsive to things they can see. Unfortunately, the accumulation of greenhouse gases in the atmosphere is invisible. Nevertheless, visuals can be used in climate litigation do display the effects of climate change and tell the story.

Resources: Making the (In)Visible Powerful: Leveraging Climate Visuals in Courts, OpenGlobal Rights

Use Amicus Curiae
Judges are often generalists, not specialists, meaning they hear cases on many areas of the law. Judges rely on briefs in order to understand the relevant case and statutes in a given case.

Amicus curiae, or "friend of the court" briefs, are a way for third parties to educate judges on the relevant law, principles, and precedents in climate litigation.

Including amicus curiae briefs from supportive partners is a wise climate litigation strategy.

Resources: See our Amicus curiae briefs page

Principles that may support Climate Litigation
The following principles have been used to strengthen demands:
 * Principle of Caution: The precautionary principle requires us to take appropriate measures to prevent harm in the event of a threat to the environment or health and in a situation of scientific uncertainty.
 * Prevention Principle: This principle is based on the and the responsibility of States to ensure that activities within their jurisdiction or control do not cause damage to the environment of other States or of areas beyond the limits of national jurisdiction. This is recognized in principle 2 of the RIO DECLARATION ON ENVIRONMENT AND DEVELOPMENT.
 * The Polluter Pays Principle, Principle 16 of RIO DECLARATION ON ENVIRONMENT AND DEVELOPMENT recognize this principle since it states that national authorities should endeavor to promote the internalization of environmental costs and the use of economic instruments, taking into account the approach that the polluter should, in principle, bear the cost of pollution, with due regard to the public interest and without distorting international trade and investment.
 * Sustainable Development
 * To learn more about legal principles that can be used to protect the environment, consult ENVIRONMENTAL LEGAL PRINCIPLES FOR ECOLOGICALLY SUSTAINABLE DEVELOPMENT(Spanish)..