A federal appeals court on Tuesday reversed a decision the Environmental Protection Agency took nearly a decade ago, which may result in livestock farmers coming under more scrutiny for their air emissions under President Trump.

The D.C. Circuit Court of Appeals ruled that the EPA, under former President George W. Bush, erred when it exempted most farms from having to report air pollution from hog and cattle waste.

"We have no doubt that a desire for efficiency motivated some of the exceptions Congress provided, but those concerns don't give the agency carte blanche to ignore the statute whenever it decides the reporting requirements aren't worth the trouble," Judge Stephen Williams wrote in the court's decision.

The EPA carved out the exemption for farms in 2008. It allowed most farms that raise and harvest livestock not to be required to report ammonia and hydrogen sulfide emissions from the tons of waste the animals produce. The emissions tracking falls under EPA's Clean Air Act authority.

Most farms do not have to comply with the air law with the exemption in place, but they still must follow local ordinances to ensure communities are protected. Nevertheless, Tuesday's order could mean farmers will be coming under new requirements to monitor and report their emissions and be made subject to EPA enforcement authority.

All three judges in Tuesday's ruling agreed with Williams that the EPA was wrong in granting the exemption to farmers. Williams was appointed under former President Ronald Reagan.

The case was brought to the court by environmental groups that opposed the exemption.

It is not clear if the EPA or the Justice Department under Trump will seek to appeal the ruling.