Justice Department moved to dismiss NAACP's Clean Air Act suit against Musk's xAI, citing national security

On June 15, 2026, the U.S. Department of Justice filed a motion in the U.S. District Court for the Northern District of Mississippi to intervene in and dismiss the NAACP's Clean Air Act citizen lawsuit against Elon Musk's xAI Corp. and its subsidiary MZX Tech LLC. The NAACP, represented by Earthjustice and the Southern Environmental Law Center, had sued xAI in April 2026 alleging the company installed at least 57 methane gas turbines in Southaven, Mississippi—near homes and schools in majority-Black neighborhoods on the Mississippi-Tennessee border—without securing required air pollution permits under the Clean Air Act. The turbines power the Colossus 2 data center and emit nitrogen oxides and other pollutants linked to asthma, respiratory illness, and premature death.

The DOJ's Environment and Natural Resources Division argued in its motion that the NAACP's suit "threatens American national, economic, and energy security by seeking to shut off the power supply for artificial-intelligence innovation that supports the Department of War's military operations." The Department cited a declaration from the Pentagon's Chief Digital and Artificial Intelligence Officer stating that xAI's Grok AI models had been used to deploy over 2,000 munitions to 2,000 distinct targets during operations against Iran. The motion also argued the Clean Air Act does not permit citizen suits seeking relief the federal government chooses to forgo, contending the lawsuit would "cede principal enforcement authority to the NAACP."

Environmental law experts described the intervention as unprecedented. Harvard Law School senior staff attorney Erika Kranz wrote that it marked the first time the United States had moved to dismiss a citizen suit against a private defendant under the Clean Air Act. Columbia Law professor Michael Gerrard called the move "highly unusual," noting the DOJ was not disputing the underlying pollution allegations but instead making a constitutional claim that citizen suits cannot override executive enforcement discretion. Musk, whose SpaceX company owns xAI, had become the world's first trillionaire the prior week following SpaceX's IPO. The Southern Environmental Law Center described the DOJ action as a "massive power grab" that would turn communities into "sacrifice zones."