Today, a U.S. Supreme Court ruling once again affirmed the Environmental Protection Agency as the most rightful and authorized regulator of climate change pollution in the land.

While some in Congress have been trying to take this power away from the EPA, and have been attempting to block EPA controls on climate change pollution, the Supreme Court today ruled that the EPA -- not the Supreme Court, not states and not Congress -- is "best suited to serve as primary regulator of greenhouse gas emissions."

In its decision today, the court rejected a lawsuit brought by several states, New York City and several environmental groups against American Electric Power and some of the nation's biggest and most polluting power utilities for their excessive greenhouse gas emissions, harmful pollutants known to cause climate change.

The court's reason for rejecting the case was that states and citizens must not be suing individual climate change polluters because the federal government -- through the EPA -- must be protecting all citizens from climate change pollution regardless of what state they are in. In other words, this harmful pollution is a matter for the national EPA to resolve, not specific courts or states. So while citizens of those five states on the lawsuit lost today, the citizens of every state in America win.

It's true that this powerful decision won't stop some in Congress from trying to stand in the way of these science- and health-based pollution protections, but nevertheless, this ruling is a win for the Obama administration and the EPA, which has been moving to rein in the nation's biggest climate change polluters.

The decision should embolden and hasten President Obama and EPA Administrator Lisa Jackson to finish the job they started and quickly finalize these crucial pollution reductions so that we are all protected from dangerous climate change pollution.

“This decision clearly puts the ball in the Obama administration’s court to move forward on reining in climate change pollution without delay," said Earthjustice managing attorney David Baron today when the news broke.

The first time the Supreme Court ruled on climate change, in its 2007 Massachusetts v. EPA decision, the Court established EPA's authority to curb climate change pollution under the Clean Air Act. Earthjustice was co-counsel in the 2007 case, and is now intervening in defense of limits on greenhouse gas emissions from cars and trucks, which the EPA adopted in the wake of that case.

“Today’s Supreme Court decision highlights how crucial it is for EPA to set strong national limits on climate change pollution from power plants and other large industrial plants," added Baron.