The Supreme Court ruled 5-4 that carbon dioxide is an air pollutant and the Environmental Protection Agency (EPA) must regulate CO2 emissions.

For many years, the EPA maintained its position that CO2 was not an air pollutant, because its there in the air we breath and, therefore, the EPA could not regulate CO2 under the guidelines of the Clean Air Act.

Thirteen states, California, Connecticutt, Illinois, Rhode Island, Maine, Massachusetts, New Jersey, New Mexico, New York, Oregon, Vermont and Washington along with the cities of Baltimore, New York and Washington DC joined in a lawsuit against the EPA to require that CO2 emissions be considered when reviewing air permits. After four years, the Supreme Court ruled against the EPA and struck down the EPA’s ruling that it didn’t have any power to regulate CO2.