Most accounts have the SCOTUS letting democracy down today. But a decision back in 2007 may provide some relief for the planet by giving President room to enact meaningful change despite conservative obstruction. A centerpiece of the plan will rely on a ruling giving the EPA the power to regulate carbon dioxide

Wonkblog — The details of these rules will matter a great deal — and the agency has some leeway on how strict they’ll be. One group, the Natural Resources Defense Council, has outlined a proposal for deep cuts. The EPA would set different overall emissions goals for each state, and power companies would have to figure out how to meet them through a combination of efficiency, less coal use or renewable power. NRDC estimates that the United States could cut carbon emissions an additional 10 percent by 2020 this way.

But it’s not clear how strict the agency will actually go with its power-plant rule. Many utilities are likely to oppose an aggressive proposal, which NRDC expects to cost some $4 billion per year. And plenty of coal-state governors oppose the new rules, worrying that they could hike electric bills for consumers. What’s more, using the Clean Air Act to regulate carbon dioxide could prove legally dicey, especially if the EPA pursues sharp cuts.

“Pretty much everything the EPA could do on carbon would be under parts of the Clean Air Act that haven’t really been tested,” says Nathan Richardson, an attorney at Resources for the Future. He notes that the safest approach, legally, would be for the EPA to require coal plants to adopt the most efficient technologies available and let states hash out the details. But that could also have a smaller effect on emissions.