Right-leaning legal activists along with Elon Musk’s artificial intelligence company have brought sweeping challenges against a cornerstone of legal enforcement in the United States: the right of private groups, people and local governments to sue over violations of many major laws.

Their argument, supported by the Trump administration, is that the Constitution reserves tremendous power for the president and federal agencies to decide how — or whether at all — to enforce federal law. They contend Congress should never have handed that power to others through so-called citizen suits that are part of environmental, campaign finance and certain other laws.

Environmentalists say it would be devastating to lose this essential, decades-old tool that is used to impose fines and halt lawbreaking by bad actors. Citizen suits, for example, have extracted millions from heavily polluting oil and gas operations, and ensured that lead pipes in Flint, Michigan, would be removed after its water crisis.

Legal experts say four pending federal cases — one of them filed last week — are moving forward at a time when the conservative majority on the Supreme Court gives opponents of citizen suits a greater chance than ever of success. The hard part for those opponents now is winning early federal cases and creating disagreement between the country’s appeals courts, which may help convince the Supreme Court the issue is important enough for a nationwide ruling.

Back in 2000, a Supreme Court opinion opened the door for that possibility.

“Many of us who worked in this area have been waiting basically 26 years for this shoe to drop,” said Richard Lazarus, a Harvard professor with decades of experience in environmental law.

Lazarus was referring to former moderate Justice Anthony Kennedy’s comments in a Clean Water Act case that citizen suits raised “difficult and fundamental” questions about whether they improperly dilute executive power. The late conservative Justice Antonin Scalia wrote in a dissenting opinion in the same case that citizen suits turn “over to private citizens the function of enforcing the law.” He avoided explicitly saying they were constitutional.

“The court is more like Scalia’s court since he died than it ever was when he was there,” said Lazarus.

He observed that those who lost cases where Scalia dissented are rushing back to today’s court hoping for a more favorable result.

The critical issue for citizen suits is who — the government or private citizens — collects fines and has control. A person filing a citizen suit must tell the government ahead of time. The government can stop the suit if it sufficiently pursues the case itself, but its options are limited and the person suing can stay involved. Citizen suits can force compliance with the law and result in fines, which go to the U.S. Treasury.

Twenty-five states sued the Trump administration Monday over its latest tariffs, calling them a pretext for replacing import taxes the Supreme Court struck down in February.

The United States last month imposed double-digit tariffs on 59 countries and the European Union, charging that they had not done enough to crack down on imports produced by forced labor. The new tariffs took effect just as the clock ran out on temporary tariffs President Donald Trump had turned to after the Supreme Court defeat.

“After losing at the Supreme Court, the administration is once again trying to illegally raise taxes on families and businesses with a new round of tariffs,” said New York Attorney General Letitia James.

Joining New York in the lawsuit announced Monday are Arizona, California, Colorado, Connecticut, Delaware, Hawaii, Illinois, Kentucky, Massachusetts, Maryland, Maine, Michigan, Minnesota, Nevada, New Jersey, New Mexico, North Carolina, Oregon, Pennsylvania, Rhode Island, Virginia, Vermont, Washington and Wisconsin.

Trump, who argues that high tariffs will revive American manufacturing, last year overturned decades of U.S. policy that favored lower tariffs and ever-freer trade. Invoking the 1977 International Emergency Economic Powers Act, or IEEPA, he imposed double-digit tariffs on imports from almost every country, saying America’s longstanding trade deficit amounted to a national emergency.

But the Supreme Court ruled that IEEPA did not authorize tariffs. The decision forced the administration to send refunds to importers who’d paid the tariffs. Eager to make up the lost revenue, Trump turned to temporary 10% worldwide tariffs. But they expired at midnight July 24.

Now he’s tapping more durable tariffs under Section 301 of the Trade Act of 1974, which permits the president to impose import taxes and other sanctions against countries found to engage in unfair trade practices. Trump used Section 301 to impose big tariffs on China in his first term, and they survived court challenges.

The U.S. Federal Communications Commission is banning imports of new foreign-made humanoid robots and power inverters, citing national security risks, in a move that targets China. Beijing quickly accused the U.S. of protectionism.

The measures are likely to test relations with Beijing ahead of a planned U.S. visit by Chinese leader Xi Jinping to meet with U.S. President Donald Trump in September. China dominates the global market for humanoid robots with an estimated market share of roughly 85%.

The FCC’s ban also includes new imports of quadruped robots, often referred to as four-legged robot dogs. The agency said imports of advanced robots pose cybersecurity and other national security risks. Offshore production of such equipment also leaves U.S. supply chains vulnerable to disruptions.

The ban on power inverters, which are used to convert direct current (DC) electricity into alternating current (AC) electricity and are used in renewable energy systems, data centers and household appliances, could have sweeping ramifications.

This is the latest in US restrictions on Chinese imports.

FCC chairperson Brendan Carr said Tuesday that the move was to “secure America’s critical supply chains.” He said the bans apply to “new versions” of such imports.

The FCC’s bans follow a slew of U.S. restrictions on imports of Chinese products, including drones, and on exports of U.S. advanced technology to China.

The U.S. is also weighing controls on use of Chinese open-source artificial intelligence models at a time when Chinese AI is rapidly gaining ground.

“It’s a steady drumbeat of potential flashpoints heading into (the) Trump-Xi summit planned for September,” said Samm Sacks, a senior fellow at the New America think tank focused on Chinese technology policies.

China has been rapidly expanding the use of robots, with policies supporting its technology sector. Morgan Stanley analysts forecast its market for humanoids could reach $15 billion by 2030.

“Chinese manufacturers have been scaling production and reducing costs faster than most overseas competitors,” said analyst Kangyuxiao Li at Morningstar.

“Restricting their access to the U.S. removes an important future market and protects U.S. developers from potential price competition,” he said. “However, it will not materially slow China’s overall humanoid development, given the size of its domestic manufacturing base and opportunities in other export markets.”

Of the around 15,000 humanoid robots shipped globally in 2025, Unitree and AGIBOT, two of China’s largest advanced robotics companies, each shipped more than 5,000. Their U.S. counterparts, like Tesla and Figure AI, each shipped a few hundred or less, according to the technology research and advisory group Omdia.

On the restrictions on power inverters, Cheng Wang, another Morningstar analyst, said the pressure on U.S. markets should be limited. The ban appears to not impact the continued use of existing devices nor the selling by Chinese companies of models that were previously approved by the United States.

A federal appeals court on Tuesday ended more than 60 years of federal oversight of a Louisiana school system that had been ordered to eradicate segregation.

The 5th U.S. Circuit Court of Appeals lifted a decades-old desegregation mandate for the Concordia Parish School Board, handing a victory to President Donald Trump's administration, which has pushed to end the court-ordered plans. The school system has been a focal point in the administration's attempt to end legal cases dating to the Civil Rights era.

The U.S. Justice Department spent decades fighting for such cases but reversed course under Trump. Officials in his administration have framed the remaining segregation orders as federal intrusion into local school systems. Louisiana officials agree they're no longer needed and describe them as relics of a time when Black students were once forbidden from attending some schools.

"The good people of Concordia Parish elected their school board to govern their schools — not unelected federal judges," Louisiana Attorney General Liz Murrill said in announcing the ruling. "Today's decision puts that authority back where it belongs."

Members of the Concordia Parish School Board did not immediately respond Tuesday to emails seeking comment.

Families who brought the suit are no longer involved.

The Concordia Parish case dates to 1965, when the area was segregated and home to a violent offshoot of the Ku Klux Klan. Black families in Ferriday, a town on the central-eastern border of Louisiana, sued for access to all-white schools, and the federal government intervened. As the district integrated its schools, many white families fled Ferriday.

The district's schools came to reflect the demographics of their surrounding areas. Ferriday is still mostly Black and low-income, while neighboring Vidalia is mostly white and takes in tax revenue from a hydroelectric plant.

Some parents and civil rights groups have argued that desegregation orders remain important tools to address vestiges of segregation such as racial disparities in student discipline, academic programs and teacher hiring.

The Concordia Parish order was used to force a mostly white charter school that opened in 2013 to prioritize Black students and create a more integrated student body.