President Barack Obama's plan to use federal agencies, and the Environmental Protection Agency in particular, to drive his second-term climate change agenda might be in peril if he cannot fill vacant seats on the federal court that has jurisdiction over major national regulations, legal experts say.
Obama is the first full-term president in more than a half century not to have appointed a single judge to the powerful U.S. Court of Appeals for the District of Columbia Circuit.
The court, considered the second most important in the nation, decides cases challenging agency regulations such as those involving the EPA's Clean Air Act and often serves as a feeder to the Supreme Court.
New York attorney Caitlin Halligan, Obama's first nominee to fill one of four vacant seats on the 11-judge bench, announced her withdrawal on Friday after Republicans twice blocked her nomination over concerns about a 2001 case in which she represented New York state and argued that gun manufacturers had created a "public nuisance" under state law.
Obama said in a statement on Friday that he was "deeply disappointed" that a minority of senators continued to block an up-or-down vote on her nomination after two and a half years.
Meanwhile, Obama's second pick, former corporate lawyer Sri Srinivasan, will have a Senate Judiciary Committee hearing in the next few weeks after being delayed in 2012 by Republican requests for more information about his role in the settlement of a housing act case as a U.S. deputy solicitor general.
While some fault Republicans for slow-walking the appointment of judges that would shift the balance of the court to Democrat-appointed judges, others fault Obama for not taking advantage of the now-four open seats and making judicial appointments a political priority. Two of the four vacant seats have been open since Obama came into office in January 2009. The seat Halligan was nominated for has been vacant since 2005.
Some legal experts warn that under the status quo - four Republican appointees and three Democratic appointees among active judges - Obama's plan to bypass a deeply partisan Congress to address climate change using existing authorities will not be easy.
"There is really no moving forward with regulation without going to the DC Circuit and the decision of the court could really have major consequences," said Michael Livermore, executive director of the Institute for Policy Integrity at New York University's law school.
The court hears all challenges to government agency regulations.
And regardless of the political balance, some warn the short-staffed court will have a hard time handling a growing case load of challenges to increasingly complex EPA regulations.
"There is a reason why there are 11 judges on that court of appeals," said John Cruden, director of the Environmental Law Institute. "They (cases) will take longer to resolve than they are right now because they are more complicated and they require and demand a lot of attention."
A former D.C. circuit judge on the court from 1979 to 1999 last month termed the ongoing vacancies a cause of "extreme concern" because the court lacks the manpower to carry out its "weighty mandate," which includes cases ranging from environmental protection to civil rights to national security.
Patricia Wald, who was an appointee of Democratic President Jimmy Carter, wrote in a February 28 op-ed in the Washington Post that the number of pending cases per judge has grown to 188 today from 119 in 2005.
Although the court's six senior status judges can hear cases, they cannot participate in re-hearings. Five of those six judges are Republican appointees.
Obama said in his February State of the Union address that he would direct his cabinet to take steps to curb carbon emissions if lawmakers fail to enact legislation - a likely outcome in the deeply divided Congress.
The EPA is expected to be at the center of Obama's climate efforts. It is due this year to finalize emissions standards for new power plants and industrial facilities. After that, it will set a standard for the country's power plants and industrial sources that account for nearly 40 percent of domestic emissions.
The proposed regulations will almost certainly be challenged by industry, including electric utility companies and manufacturers, who argue the agency is wrongly interpreting the Clean Air Act to write its standards.
"He (Obama) can lean as heavily as he wants on the EPA and its all for nothing if he gets the wrong panel reviewing what they do," said Tom McGarity, a law professor at the University of Texas law school in Austin, who specializes in environmental and administrative law.
Three-judge panels are assigned randomly to resolve cases brought to the court. With just seven active judges, many of the same judges will deliberate similar EPA challenges.
Some analysts say the court has become more polarized on these issues, making the outcome largely dependent on the panel that gets selected - a roll of the dice.
Some also expect delays or revisions to the EPA's proposed standard for new power plants beyond an April 13 deadline as the agency anticipates inevitable challenges in the DC circuit and uncertainty about how the judges will rule.
"It's certainly possible that the EPA has recognized that it needs to be a little less aggressive in its interpretation and implementation of its authority," said Jonathan Adler, a law professor at Case Western Reserve University.
Recent setbacks in the DC circuit might have reminded EPA that its technical and legal analysis needs to be bullet proof.
One such loss was the court's 2-1 decision in August to strike down an EPA rule to curb sulfur dioxide and nitrogen oxide emissions from power plants that cause acid rain and smog across state lines. The decision called on the agency to rewrite the rules, a process that could take years.
Two of the three judges ruling on the case said the EPA exceeded its "jurisdictional limits" in interpreting the Clean Air Act. The EPA asked for a full-court hearing in January but it was denied.
The court ruled more favorably for the EPA in June, though, when it upheld agency rules on greenhouse gas emissions, including the scientific justification to regulate them because they endanger public health.
But new standards for power plants, mercury and hazardous materials, ozone rules and other controversial regulations will face uncertain fates in the court if the status quo continues.
NYU's Livermore said that, while recent decisions on the EPA's interpretation of the Clean Air Act have been mixed, the court has clearly demonstrated it is not afraid to strike down rules and send the agency back to the drawing board.
"This is not a court that is afraid to act and use its powers. There is no getting around these guys. It is small, so one or two judges can make a big difference in the ultimate decision," he said.
Observers say Obama needs to make more nominations for the court or broker a deal with Republicans to get at least some of his judicial picks confirmed, or he will risk missing out on a chance to leave his mark on the court.
"If we continue on the current path of invalidating critically important rules, the DC circuit will be the graveyard for all programs, initiatives that are being pushed by the Obama administration and will affect all of us," said Nan Aron, president of the judicial rights group Alliance for Justice.
"The DC circuit has that much power."