The United States Chamber of Commerce has come out in support of a bill, HR 6666. The bill, if it passes through Congress, would amend the Clean Air Act so that carbon dioxide and other greenhouse gases are not able to be regulated. It would amend the Clean Air Act to read, “The term ‘air pollutant’ shall not include carbon dioxide, water vapor, methane, or chloroflourocarbons.” It would in effect overturn the Supreme Court’s ruling from a year ago in Massachusetts v. EPA, which held that the Environmental Protection Agency (EPA) must regulate GHG emissions under the Clean Air Act if it finds that those emissions are reasonably likely to endanger public welfare.