Many U.S. vehicle manufacturers have said they would like to see a national standard for emissions, instead of the current system of different standards in every state.
Today the EPA responded to the Supreme Court decision with a defense of the Bush administration's climate change policy.
"EPA is reviewing the Court's decision to determine the appropriate course of action," said Jennifer Wood, press secretary for the EPA.
"The Bush Administration has an unparalleled financial, international and domestic commitment to reducing greenhouse gas emissions," Wood said, arguing the administration has a goal to reduce greenhouse gas intensity 18 percent by 2012.
"The president's policy achieves near-term reductions, while investing in long-term solutions," she said.
During a White House press briefing today, deputy press secretary Dana Perino argued the administration has already tried to reduce carbon dioxide emissions by increasing mileage standards for light trucks and SUVs through the Department of Transportation's CAFE program.
"The way to get cars to be more efficient is to burn less gas and to go more miles and that's what we've been working to do," said Perino.
When asked why the administration has declined to mandate that businesses cap their greenhouse gas emissions, Perino said, "we did not move forward with a full, mandatory cap because we believe that it would have been harmful to United States businesses."
"Everyone is emitting up into the air," said Perino, "and if there are no actions taken by the major developing countries, like China and India ... you're going to put the American economy at a great disadvantage, push American businesses overseas, and then do nothing for the environment," she said.
Dissenters of the Supreme Court decision included some of the more conservative justices, including Justices Scalia, Clarence Thomas, Samuel Alito and Chief Justice John Roberts.
The dissenting Justices questioned whether concern over global warming is warranted.
"The Court's alarm over global warming may or may not be justified, but it ought not distort the outcome of this litigation," wrote Justice Scalia in his dissension.
"No matter how important the underlying policy issues at stake, this Court has no business substituting its own desired outcome for the reasoned judgment of the responsible agency," wrote Scalia.
Eleven states joined Massachusetts in bringing the suit against the EPA, including California, Connecticut, Illinois, Maine, Massachusetts, New Jersey, New Mexico, New York, Oregon, Rhode Island, Vermont and Washington State, along with numerous other environmental groups and nonprofit organizations.
Fourteen "friend of the court" briefs were also filed from independent scientists, former EPA administrators, former Secretary of State Madeleine Albright, electric power companies, state and local governments, and others.
However, some of those same groups say it may be years before any real change is taken by the EPA.
"It puts a process into motion that essentially compels the EPA to at some point issue regulations on carbon dioxide," said Dorner. "I think, obviously, that process will be a slow one and we might see some action in Congress before that process comes to full fruition. It just moves things down the field one more step."