Milkey faced skeptical questioning from Chief Justice John G. Roberts Jr. and Justice Samuel A. Alito Jr., the court's newest members, but the most sustained -- and entertaining -- interrogation came from Scalia.
At one point, he acknowledged the role of carbon dioxide as a pollutant in the air but wondered about it being a pollutant in the "stratosphere."
"Respectfully, Your Honor, it is not the stratosphere. It's the troposphere," Milkey said.
"Troposphere, whatever. I told you before I'm not a scientist," Scalia said to laughter. "That's why I don't want to have to deal with global warming, to tell you the truth."
Justice Stephen G. Breyer said a change of heart by the EPA could set off a string of similarly small decisions by other agencies, "each of which has an impact, and lo and behold, Cape Cod is saved." He seemed most sympathetic to the states' case, along with Justices John Paul Stevens, David H. Souter and Ruth Bader Ginsburg.
Justice Clarence Thomas, who as usual asked no questions, is presumed to be in line with Scalia, Roberts and Alito. That leaves Justice Anthony M. Kennedy as a pivotal vote in whether the states have proven they have standing for the case to go forward.
The title "Your Honor" sort of loses all meaning when it's used in reference to Scalia, doesn't it?