In an amicus brief filed to the U.S. Court of Appeals for the D.C. Circuit in American Lung Association v. U.S. Environmental Protection Agency, Sean Hecht and Berkeley Law's Ted Lamm argue the Affordable Clean Energy Rule is directly opposed to what Congress intended, and said, when it crafted the Clean Air Act.

Their client, Tom Jorling, is a renowned Clean Air Act expert who served as a staffer on the Senate committee that drafted and negotiated the pivotal 1970 amendments that form today’s law.

On May 18, 2020, Emmett Institute supervising attorney and project director Julia Stein and co-executive director Sean Hecht filed a comment letter to EPA on behalf of 100 U.S. law professors urging the agency to withdraw its revamped “Transparency in Science” rule. As written, the rule would foreclose EPA’s ability to rely on important peer-reviewed scientific studies that inform key environmental protections, like safe drinking water standards and pesticide regulations, where the underlying data supporting those studies are not publicly available.

On July 1, 2020, Sean Hecht and Ted Lamm of Berkeley Law filed a brief on behalf of the National Parks Conservation Association and the Coalition to Protect America’s National Parks in Union of Concerned Scientists, et al. v. National Highway Traffic Safety Administration. The authors show that climate change- and air pollution-related harms occurring in California's National Parks provide direct evidence of the compelling and extraordinary conditions that justify California’s vehicle emissions program.