It was a landmark ruling by any measure. On April 2, 2007, the Supreme Court ruled that the Environmental Protection Agency had the authority to regulate greenhouse gas emissions, and that it had to act. The justices made the choice clear: the agency had to determine whether greenhouse gases contribute to climate change or not. Environmental groups exulted that, after several years of stalling, the administration would finally be forced to do something.

Except that they didn't. Nearly a year after that ruling, which required the EPA to make a decision, the agency still hasn't. And with Administrator Stephen Johnson at the helm, there's no sign that it's going to happen anytime soon.

This is made all the more remarkable by the fact that Johnson, in blocking California's attempt to regulate greenhouse gases, has made it clear that the EPA considers them pollutants. As Georgetown Law professor Lisa Heinzerling, who wrote the lead brief in the Supreme Court case, Massachusetts v. EPA argues, "Johnson concluded that California's problems aren't "compelling and extraordinary" because they're no worse than the very bad problems the rest of the country faces as a result of climate change." That reasoning, she says, made explicit the EPA's view "that greenhouse gases endanger public health and welfare." That leaves Johnson with no choice, she writes.

But Johnson is a stubborn opponent. Yesterday, Sen. Dianne Feinstein (D-CA) asked Johnson a simple question during a Senate appropriations subcommittee hearing: How many staff at the EPA does he have working on this? Johnson, a Zen master of digression, mind numbing minutiae ("gobbledygook"), and generally thwarting questioners, never gives a simple answer. Here's the video:

After a digression covering Judge Antonin Scalia's minority opinion and all the other things that the EPA is considering ("I can go on and on"), Feinstein had had it.

"Let me ask you this... all right let me ask you this question. How many personnel right now are working on the endangerment finding?"

"I don't know specifically at this time how many people are or are not working on specific pieces of our work...."

"Well, we've been told no one is working on it currently," she responded.

"I would have to check."

When Feinstein pressed, Johnson admitted that "I don't know the answer to that," but offered he himself is working on it, determining "what are the next steps."

Finally, Feinstein concluded, "Then I've got to believe you're stonewalling."

"Madam Chairman, I am not stonewalling," was his rather unconvincing response.

Environmental groups aren't taking him at his word. In a letter to Johnson on January, 23rd signed by a number of groups, including Sierra Club and Greenpeace, they demanded that he indicate by late February when he would be complying with the Supreme Court ruling. If he can't do that, they wrote, then they'll be forced to go back to court.

Obviously, that hasn't happened. Johnson doesn't have "a specific timeline," the EPA responded. So the groups will most likely return to court "literally any day now," Sean Siperstein of the Community Rights Counsel told me.

When asked if the Massachusetts attorney general would be returning to court as well, a spokeswoman for Attorney General Martha Coakley's office responded "We are aware of the Administrator’s statements and are reviewing are options.“

There's actually evidence that Johnson has gone backwards since last year. Written answers to questions from Sen. Feinstein indicated that "three to four staff members" had worked on the issue last year. Now, apparently, no one (well, besides Johnson) is. The only excuse Johnson has mustered is that the energy bill the president signed into law last year has thrown his analysis into confusion. The environmental groups dismiss that argument out of hand, saying the bill changed unrelated language in the Clean Air Act.

Instead, they say, Johnson is stalling to protect the administration and the auto industry. "The longer they can stave off regulation, the better it is for them," Josh Dorner of the Sierra Club told me.

"I think it’s stunning," he said. "After seven years after being constantly outraged by any number of things, to just ignore the Supreme Court, that's just on a whole other level to me."