On April 5, Gov. Gavin Newsom’s administration filed suit in federal court to try to compel two federal agencies to provide the underlying data and analysis used to support a rollback of federal vehicle emission standards that Newsom said threatens the air quality and health of millions of Californians.

The suit, which was filed by Attorney General Xavier Becerra on behalf of the Newsom administration and California Air Resources Board, claims that the U.S. Environmental Protection Agency and the National Highway Traffic Safety Administration failed to comply with CARB’s Freedom of Information Act request filed in early September. In addition, the NHTSA failed to respond to an appeal filed by the state in December, and the lawsuit requests that the court compel the Trump Administration to provide the information and to decide whether the federal government may keep that information hidden, the Newsom administration said.

“The Trump administration is willfully withholding information on their ill-advised rollback of federal vehicle emission standards because there is simply no science or logic to back up their actions,” Newsom said.

In August, the Trump administration announced that in place of requirements to increase vehicle fuel efficiency and reduce greenhouse gas emissions, it proposed to freeze the standards at the 2020 level through the 2026 model year. The administration’s proposal would likely also block many other states that use California standards from moving forward, the Newsom administration said.

If California were required to follow the federal rollback proposal, global warming emissions could increase by almost 15 million metric tons per year by 2025, an amount that is roughly equivalent to putting an additional 2.8 million cars on the state’s roads for a year, the Newsom administration said.

New York has a similar lawsuit over NHTSA and EPA’s failure to comply with the state’s FOIA request. That lawsuit is currently pending in the U.S. District Court for the Southern District of New York.