In January, five members of UCLA School of Law’s Emmett Institute on Climate Change and the Environment and Frank G. Wells Environmental Law Clinic submitted an amicus brief to the U.S. Court of Appeals for the D.C. Circuit, challenging the Trump administration’s rollback of federal vehicle pollution and fuel economy standards.

On November 25, 2019, Emmett Institute faculty members Sean Hecht and Harjot Kaur submitted a comment letter to the Environmental Protection Agency in response to the Proposed Policy Amendments 2012 and 2016 New Source Performance Standards for the Oil and Natural Gas Industry (the "Proposed Rule").