Trump v. Sierra Club

President Donald Trump ran for office in 2016 on a promise that Mexico would pay for his plans to expand a wall along the border between the United States and Mexico. Since becoming President, he obtained more than $15 billion in federal funds for the border wall project, including $5 billion provided by Congress through conventional appropriations and $10 billion from Pentagon accounts. In 2019, the Supreme Court allowed the administration to proceed with the transfers and contracts for construction, over objections by House Democrats, affected states, and environmental groups. Then, in July 2020, a panel of the U.S. Court of Appeals for the Ninth Circuit held that it was unlawful for the administration to use funds intended for the Department of Defense on the wall instead, but the Supreme Court refused to block President Trump from using the funds while litigation continued.