( CNN ) -- It is a familiar tactical strategy at the Supreme Court : when an oral argument gets too dense over regulatory interpretation -- turn it into a sports analogy . An Obama administration lawyer did that Tuesday in closely watched environmental appeal , comparing federal efforts aimed at curbing air pollution to basketball scores . The court seemed impressed , with Chief Justice John Roberts calling it a `` pretty good '' analogy . After that the athletic aphorisms just would not stop . At issue is whether an `` upwind '' state that is polluting a `` downwind '' state is free of any obligations under the so-called Good Neighbor provision , unless and until federal regulators have quantified the upwind state 's contribution to downwind state 's air pollution problems . The case is an important test of federal regulatory power , and the rules issued two years ago by the Environmental Protection Agency are being challenged by a coalition of 15 states , as well as several energy companies and labor unions . Leaders in some mostly conservative states say lost jobs and higher energy costs are at stake from what they see as arbitrary and ambiguous regulations . But the administration and its environmental allies counter Americans ' health should come first , and that as many as 45,000 deaths could be prevented each year if the Cross-State Pollution Rule would be allowed to go into effect . Overall , it appeared the EPA may prevail in the complex regulatory case , based on the comments from the justices during 90 minutes of arguments . It would be a rare environmental victory in a conservative majority court , if that were to occur . The arguments come just hours after eight of nine governors from the affected downwind states signed a petition urging the EPA to force nine southern and midwestern upwind states to reduce smog and soot emissions from power plants . The one downwind governor who did not sign was Gov . Chris Christie , the New Jersey Republican . Those Democratic or Independent governors criticized a federal appeals court ruling last year against federal oversight , saying it `` allows upwind states to postpone the costs of air pollution controls for years , while in the interim downwind states and their residents are forced to suffer the present consequences of that pollution . '' Enforcement of what is known as the Transport Rule was adopted by the EPA in 2011 , but remains on hold while the court cases work toward a final conclusion . In Tuesday 's session , Justice Department lawyer Malcolm Stewart got the ball rolling when he said the EPA should be allowed to use the somewhat discretionary standard `` contribute significantly , '' when determining a state 's cost-based share of transported air pollution . `` There are various reasons to think that EPA reasonably construed that term to include a component of difficulty of achievement , '' he said of a downwind state 's inability to comply , in the face of continuing pollution from its neighbors . `` We might say that dunking a basketball is a more significant achievement for somebody who is 5 feet 10 than for somebody who is 6 feet 10 . '' Roberts took up the challenge when sharply questioning the lawyer representing corporate and union interests , Peter Keisler . `` If you ask the coach what significantly contributed to the loss , he 's going to talk about the missed layup rather than the missed desperation throw , '' said the chief justice , `` even though as far as amount , each was going to count for two points . '' Justice Antonin Scalia used the metaphor to turn the point on its head . `` The question you should ask the coach , when you lost 101 to 100 : which of the 101 points contributed most to your loss ? '' he asked , bringing laughter in the courtroom . `` I mean , he would not answer the one that was the layup . He 'd say what do you mean ? All of the 101 points . '' Scalia added the proposed EPA rule changes were not what Congress had in mind when it passed the landmark Clean Air Act . Adding to the sports talk , he said the agency has `` hidden the ball '' with its ambiguous standards . `` We 're not going to tell you what the target is , '' he said , relying on his own interpretation of what federal regulators are doing to some states . `` It 's up to you to come up with a SIP ( state implementation plan ) and we 'll tell you after the fact whether that SIP happened to meet the target that we 've invented . '' Among the provisions being challenged is the EPA 's cost-based formula , using what it calls a balance between an upwind state 's obligation to reduce coal-fired pollution , and the amount of money that would be required for a downwind state to feasibly meet its own obligations . That calculation was a key part of the oral argument , which critics of the policies say unfairly punishes some states more than others , by placing a greater financial burden for their share of unhealthy air particulates . Texas Solicitor General Jonathan Mitchell , representing one of the states challenging the rules told the court , `` EPA 's actions in this case have written the states out of the Clean Air Act . ... EPA has left the states completely in the dark about the meaning of the phrase 'contribute significantly . ' '' Justice Stephen Breyer called it a tough problem and questioned the upwind states ' position . `` But it 's supposed to advance the ball '' using yet another sports reference . `` So there is a procedure for the states to come in if they can come up with a better plan . That 's what you 've just heard , and so do it . So what 's arbitrary or capricious about such a system ? '' Mitchell said it was up to the EPA to issue clear guidelines before enforcing those standards , and the burden was on the federal government , not the states . Breyer , in response : `` There 's six states that contribute to the seventh state 's pollution , and how much each state can cut back depends . It depends on what it costs . It depends on how much they contribute . It depends upon what the other states will do . It depends upon where the wind blows , and that changes all the time , '' he said . The justices next February will hear a related case : can the EPA tighten emission standards for `` stationary '' greenhouse gas sources -- such as power plants -- in what the government says is an effort to stem the effects of global warming . The high court in 2007 affirmed the conclusions by much of the scientific community that greenhouse gases are an air pollutant , but that case just dealt with emissions from motor vehicles . The high court will decide if the agency properly extended its regulatory authority . The consolidated cases argued Tuesday are EPA v. EME Homer City Generation ( 12-1182 ) and American Lung Assn . v. EME Homer City Generation ( 12-1183 ) . A ruling is due in the next several months .
States that pollute are under fire from those that do n't . Fifteen states , other groups challenging new federal anti-pollution rules . Comment: Oral arguments over 90 minutes take on sports metaphor theme .