The Supreme Court proceedings in the case took place amid the backdrop of a number of high-profile mass shootings took place in the United States, including the shootings at El Paso, Texas and Dayton, Ohio, in August 2019. Sheldon Whitehouse and four other Democratic senators (Kirsten Gillibrand, Mazie Hirono, Richard Blumenthal, and Dick Durbin) filed an amicus brief that strongly urged the Court to find that the case is moot and criticized the Federalist Society and National Rifle Association for promoting what the brief called a "project" to undermine gun-control laws. Referring to the recent mass shootings, the brief said, "In the cloistered confines of this Court, and notwithstanding the public imperatives of these massacres, the NRA and its allies brashly presume, in word and deed, that they have a friendly audience for their 'project.'" The senators' brief argued that "ignoring neutral justiciability principles to reach desired outcomes" would damage the Court's legitimacy as an institution and accelerate a decrease in public faith in the judiciary, and suggested that the Court "heal itself before the public demands it be 'restructured in order to reduce the influence of politics.'"