Sri Srinivasan is one of the names being floated to fill the Supreme Court seat vacated by the death of Antonin Scalia. But the aspects of Srinivasan’s record that make him a favorite to eke out an improbable confirmation from the GOP-controlled Senate are precisely those that are considered flaws by progressives.

Before his appointment to the U.S. Court of Appeals for the District of Columbia Circuit in 2013—confirmed 97-0 by the Senate—Srinivasan built a career at a firm that defended ExxonMobil and the mining company Rio Tinto from allegations of human rights abuses in Indonesia and Papua New Guinea. This is why Jamie Henn, co-founder of the climate group 350.org, is already describing Srinivasan’s record as “mixed” and referring to the defense of ExxonMobil as “deeply disturbing,” according to Politico.

It may seem like an academic exercise to preemptively criticize Srinivasan, since the chances of him being confirmed, at this point, appear close to zero. But Obama’s short list deserves scrutiny, since one person on that list may eventually be confirmed, if not under Obama, then under a Democratic successor. Climate activists, in particular, will be watching closely. For better or worse, the next Supreme Court has the power to alter the fate of the world.

As long as Congress remains divided, it will be the Supreme Court that defines the limits of what the Environmental Protection Agency can do to combat climate change for years to come. To understand how important the Supreme Court is to shaping the U.S.’s climate change policy, it helps to look back. The EPA’s powers to fight climate change have been mostly defined, even bolstered, by a number of key cases.

The Clean Air Act, passed by Congress in 1970 and strengthened in 1990 when the climate denial movement was nascent, forms the basis of President Barack Obama’s response to climate change. But the act did not include greenhouse gases on the list of pollutants the EPA was compelled to regulate. Over the years, the court has empowered the agency to regulate such pollutants, through the way it has interpreted the Clean Air Act and the EPA’s authorities (Scalia, it’s worth noting, was often antagonistic toward the EPA).