The California Air Resources Board (CARB) on Friday filed a lawsuit against two federal agencies over data they used to justify rolling back the landmark Obama-era vehicle emission standards, accusing the Trump administration of “willfully withholding” information.

CARB sued the Environmental Protection Agency (EPA) and the National Highway Traffic Safety Administration (NHTSA) alleging failure to comply with CARB’s September 2018 Freedom of Information Act request for information that NHTSA and EPA used in proposing to roll back vehicle emission and fuel economy standards.

In the complaint, CARB said that it has exhausted all administrative remedies. CARB is asking the court to order the EPA and NHTSA to conduct searches and make available to CARB all non-exempt agency records that are responsive to CARB’s requests, as well as all reasonably segregable non-exempt portions of any responsive records deemed to be exempt, on a rolling basis as the records are located, without charging search or copying fees.

“Since releasing the proposed rule last summer, the Trump Administration has repeatedly failed to comply with California’s FOIA request, and the reason is clear: They are unwilling to admit that the facts and analysis simply do not support their desired outcome,” said CARB Chair Mary Nichols, in a press statement. “This lawsuit will break down their silence and secrecy. The public has a right to see all the facts and analysis used to support a rollback that increases oil consumption, hurts consumers, and pumps more air pollution and hundreds of million tons of climate-changing gases into the atmosphere.”