The Texas Commission on Environmental Quality is appealing a lawsuit that it has already won — one that was filed by children. Environmental advocates say the appeal shows that the state will go to any lengths to fight the suggestion that it address climate change.

As part of a national environmental movement, a group of young people in 2011 demanded that the commission enact steps to reduce greenhouse gases. The agency refused, and the young people’s parents sued on their behalf.

A year later, District Judge Gisela D. Triana of Travis County ruled in the agency’s favor, saying it could use its own discretion and decide not to institute greenhouse gas regulations.

But the commission still appealed, insisting that the court did not have jurisdiction over the case to begin with and that Judge Triana had made an “improper declaratory judgment” — that Texas is responsible for protecting “all natural resources of the state including the air and atmosphere.”