Sarah J. Morath, Wake Forest University

Reducing rampant pollution across the United States was so important that when Congress passed many environmental protection laws, including the Clean Air Act, Clean Water Act and Safe Drinking Water Act, it didn’t want to leave enforcement only to the executive branch.

Congress specifically wrote into those laws ways for citizens to enforce them through the courts when the government does not act to address the problem. Called “citizen suit provisions,” those parts of the laws allow regular people and advocacy groups to sue companies they believe are violating the law. Citizens can also sue federal agencies that fail to enforce the laws.

Since the 1970s, those provisions have been used in over 2,000 lawsuits. In fact, a majority of environmental cases are citizen suit cases. Citizen suits have been used to halt the construction of dams to protect endangered species, end the injection of wastewater into groundwater, and secure US$14.2 million in civil penalties for illegal emissions from a petrochemical facility. In short, these cases have shaped modern environmental law.

Now, in a legal filing, the Trump administration is saying citizens should not be allowed to enforce environmental laws. Rather, despite what the laws say, the U.S. Department of Justice has claimed in a case involving Elon Musk’s xAI that people should be required to leave enforcement to the executive branch – even if the executive decides to take no action.

A history of success

For more than 50 years, citizen suits have been an effective part of cleaning up the environment in the U.S. The process is fairly straightforward: A person or group must send a formal notification to the person, company or agency they suspect of violating the law – with a copy to the U.S. Environmental Protection Agency. If after 60 days the problem is not rectified, the people can sue.

Citizen suits often ask the courts to order a stop to the polluting activity, payments for reducing or cleaning up the harm done, and civil penalties paid to the government. But if the government has already begun an enforcement action or is actively prosecuting the violator, a citizen suit cannot proceed.

The success of these cases depends on the ability of the plaintiff to prove a violation of the law. Violations of the Clean Water Act are somewhat easier to prove than violations of other statutes because the simple act of discharging a pollutant without a permit is a violation of the law. As a result, more citizen suit provisions have been brought under the Clean Water Act than under any other environmental statute.

In my area of research, plastic pollution, citizen suits have been used to hold plastic pellet manufacturers responsible for pollution. For example, the citizen suit provision of the Clean Water Act allowed Diane Wilson, a shrimper from Texas’ Gulf Coast, to sue Formosa Plastics in 2017 for persistent discharges of plastic pellets into Lavaca Bay, where some shrimp were caught, and which is connected to the Gulf of Mexico. In 2019, Formosa ended up settling for $50 million to pay for mitigation and remediation projects in the bay, cleaning up plastic and other pollution. Formosa also agreed to pay court costs and attorneys fees.

In another example, the environmental advocacy groups PennEnvironment and Three Rivers Waterkeeper in 2023 sued Styropek USA, which manufactured expandable polystyrene used for packaging and shipping, over pellet discharges into a western Pennsylvania creek. The pellets attracted and collected other toxic chemicals and were harming local aquatic plants and fish. In 2025, Styropek settled for $2.5 million. As part of the settlement agreement, Styropek agreed to install filters in the facility’s wastewater and stormwater systems to capture plastic pellets before they reached Raccoon Creek or the Ohio River. Styropek also had to eliminate the unauthorized discharge of plastic pellets from all of the facility’s stormwater drains.

Citizen suit provisions are not included in every law. But they have arisen in other contexts. For instance, a 2025 Texas state law seeks to restrict abortion rights and allows any citizen to sue doctors or other medical providers who perform or assist with abortions.

NAACP v. xAI

In April 2026, using the citizen suit provision of the Clean Air Act, the NAACP, a nationwide civil rights organization, sued xAI, an artificial intelligence company founded by Elon Musk, in federal court.

The NAACP alleged that xAI and a subsidiary company built and operated 27 natural gas-fired turbines in Southaven, Mississippi, without the required Clean Air Act permits. The turbines generated electricity to power xAI’s nearby Colossus 2 data center. The NAACP alleged that the gas plant released harmful pollutants, such as nitrogen oxides and formaldehyde, which can increase rates of asthma, respiratory diseases, heart problems and certain cancers.

Had xAI applied for a permit to operate the turbines under the Clean Air Act, the EPA would have required xAI to use the best available technology to reduce those emissions. But xAI never applied to the EPA for a permit.

A request from the federal government

In June 2026, the U.S. Department of Justice asked the judge to dismiss the case, claiming, among other arguments, that citizen suits cannot proceed when the federal government does not oppose the polluting behavior.

The Justice Department’s court filing cited two executive orders signed by President Donald Trump within days of the start of his second term – one declaring a “national energy emergency” and the other seeking to support “American leadership in artificial intelligence.”

According to the Justice Department, the NAACP’s lawsuit threatens “artificial intelligence innovation” and national security. The government’s filing goes on to argue that citizen lawsuits were not intended to allow everyday citizens to enforce laws in ways that go against what the federal government deems is in the public interest.

Instead, the Justice Department claimed, citizen suits should be allowed by the court only when the government fails to enforce the statute, and not when the government has decided that executive branch policy means enforcement action is contrary to the public interest.

Conflict between the government and the public

This is the first time the Justice Department has taken this position in court. But defendants and judges have questioned the constitutionality of citizen suits in the past.

Some critics, including the Trump administration, view citizen suits as a way for citizens to usurp the executive branch’s prosecutorial authority. Supporters of the citizen suit provisions, on the other hand, say they allow regular people to exercise their statutory rights to advocate for a clean and healthy environment and enforce environmental laws when the government’s efforts fall short.

Regardless of how the court rules in the NAACP case against xAI, I believe the filing from the Trump administration is another step in a broader effort to consolidate government power in the executive branch.

Sarah J. Morath, Professor of Law and Associate Dean for International Affairs, Wake Forest University

This article is republished from The Conversation under a Creative Commons license. Read the original article.