Congress has never authorized the EPA to regulate GHGs for climate change purposes.

FORBES: Reining In The EPA's Reign Of Error

Over the past three decades Congress not only has never passed any legislation to regulate climate change, but has specifically rejected legislation to give EPA the authority which it now claims.

FORBES: A Pivotal Court Challenge: America vs. the EPA

Responding to a 2007 Supreme Court decision, Ms. Jackson has invoked the Clean Air Act to regulate carbon dioxide and other gases linked to climate change.

WSJ: EPA Tangles With New Critic: Labor

What legislation gives the EPA authority to regulate vehicle fuel economy, or attach that issue to climate change?

FORBES: Magazine Article

The Obama administration, meanwhile, has scrapped its efforts to push a climate bill through Congress, and is now mulling plans for the EPA to regulate CO2 emissions via the Clean Air Act.

FORBES: Obama: Cutting CO2 Helps Economy

Thanks to the Kyoto treaty on climate change, which came into effect in February, most rich countries regulate emissions of carbon dioxide in some manner.

ECONOMIST: Buttonwood