A federal judge in Mississippi on Friday, Oct. 30, refused to throw out the NAACP's lawsuit against Elon Musk's AI company xAI over the gas turbines that power one of its data centers. The NAACP and its Mississippi State Conference sued xAI and its subsidiary MZX Tech in April. They say the companies built and run a power plant of gas-fired turbines in Southaven, Mississippi, without the permits required by the Clean Air Act, the main U.S. law on air pollution, and by Mississippi's rules under it. The plant supplies power to xAI's Colossus 2 data center in Memphis, the groups say.
xAI argued that the turbines needed no air permits. In July 2025, Mississippi's environmental agency wrote to the company that it understood each turbine would stay on a flatbed trailer and was meant to remain on site for less than 12 months, and that as long as both stayed true, the turbines were exempt from permits as "mobile" and "temporary" equipment. U.S. District Judge Debra M. Brown disagreed. Mississippi's air rules borrow a federal definition: a mobile source has to be a vehicle or a "nonroad engine," and an engine covered by federal pollution limits for stationary equipment cannot count as a nonroad engine. Those federal limits count a gas turbine as stationary if it is not meant to move, under its own power or by being towed, while it runs, even when it sits on a vehicle so it can be hauled around. Taking the groups' description of the turbines as true, each one is big enough to fall under those limits. So the plant was not exempt from permits, she ruled. The state agency, she wrote, had fairly told xAI where it stood, has shown no sign of changing its view and is not trying to penalize the company, but its letter does not bind the court or stop the NAACP from arguing otherwise. She added that it was unclear why the length of time the turbines stay on site would matter for permits.
She also rejected xAI's two other arguments. The Clean Air Act lets any person sue "on his own behalf" to enforce it, and xAI argued that this bars the NAACP from suing over harm to its members. The judge found that protecting its members from pollution also serves the NAACP's own aims as an organization, so it is suing on its own behalf. She said she knew of no court that had read those words to bar such groups, and neither side pointed to one. xAI also said such lawsuits by citizens are unconstitutional, because enforcing federal law belongs to the president and the executive branch. "Because citizen suit plaintiffs sue on their own behalf, in their own name, and seek penalties that redress harm to themselves, they are not exercising the federal government's executive power," she wrote.
At the heart of the ruling is whether gas turbines brought in on trailers to power a data center can skip the air permits a fixed power plant needs. Under Mississippi's rules, this judge said they cannot, at least for turbines as large as these. The groups' complaint says at least 27 turbines were on the site in April, able to produce at least 495 megawatts together, and that they could release about 1,700 tons a year of nitrogen oxides, a main cause of smog. The groups ask the court to bar the plant from running except as the law allows, and to impose fines of up to $124,426 a day for each violation, which would be paid to the U.S. Treasury, not to the groups. "This decision is another important victory in our effort to hold xAI accountable," said Abre' Conner, the NAACP's director of environmental and climate justice.
The ruling does not decide whether xAI broke the law. At this early stage, the judge had to accept the groups' account of the facts as true and decide only whether it makes a valid legal claim. The court has yet to rule on the groups' earlier request to stop the plant from running until it has the permits and pollution controls the law requires. Shortly before this ruling, the same court turned down a similar request from the U.S. Justice Department to end the case. SpaceX, which now owns xAI, did not immediately respond to a request for comment, according to a news report.