California has tried for years to regulate greenhouse gas emissions from vehicles.  But it’s run into two red lights.
 
First, the U.S. Environmental Protection Agency hasn’t given the state permission to set stricter standards than the federal government.  And second, major automakers challenged California’s 2004 law in court.
 
On Wednesday, U.S. District Judge Anthony Ishii ruled against car manufacturers.  He said the state does have the authority to regulate tailpipe emissions.
 
Cal-EPA spokesperson Breanda Northcutt says that puts even more pressure on the federal government.
 
Northcutt: “And the first thing they can do is grant California its waiver; and we would hope the next thing they would do is adopt similar standards for the rest of the nation.” 
 
The U.S. EPA says it’ll respond to the waiver request by the end of the year.  Automakers say a state-by-state approach would limit consumer choice.