A federal appeals court is set to hear oral arguments Thursday in an age discrimination case against Sen. Ben Nighthorse Campbell (R-Colo.) that was dismissed by a lower court on grounds that the Constitution shielded him from suit.

Potentially at stake is the provision of the Congressional Accountability Act that allows an aggrieved staffer to take his or her employer to court after having exhausted counseling and mediation requirements. Passed in 1995 just days after Republicans took control of both chambers, the much-ballyhooed CAA was Congress’ first broad measure to apply federal labor laws and anti-discrimination practices to itself.

A U.S. District judge dismissed in 2002 a lawsuit brought by Rita Bastien, a former caseworker in Campbell’s state office, before it could be heard by a jury. He ruled that she was sufficiently tied to the legislative process to trigger constitutional protection. The question now before the 10th U.S. Circuit Court of Appeals is whether that constitutional provision — which protects Members from being questioned about the “Speech or Debate in either House … in any other place” — covers personnel decisions.

“It’s a very interesting question,” said Glen Nager, a former chairman of the Office of Compliance who now works for the Washington law firm Jones, Day, Reavis & Pogue. He represents a consortium of groups, including AARP, which filed an amicus brief arguing that the Constitution “does not bar Congress from freely granting civil rights to its own employees.”

Late last month, the appeals court granted the amici permission to participate in the oral argument. Those filing the “friends of the court” brief include, along with the 35 million-member AARP, the American Federation of State, County and Municipal Employees, the National Employment Lawyers Association, the American Association of People with Disabilities, and the National Asian Pacific American Legal Consortium.

Bastien attorney John Evangelisti indicated earlier this week that he planned to give the groups a third of his time before the three-judge panel.

Although each side is granted a relatively short 15 minutes of oral arguments, Nager said it’s likely the judges will allow more time. “In contrast to the Supreme Court, which adheres rigidly to the time [constraints], most appeals courts are quite flexible on the matter. My guess is that this issue will be of great interest to the panel,” Nager said. “Compared to the bread and butter of the cases the 10th Circuit gets, it’s unusual and provocative.”

U.S. Circuit judges Stephanie Seymour (a Jimmy Carter appointee), Bobby Baldock (a Ronald Reagan appointee) and Harris Hartz (a George W. Bush appointee) will hear the case Thursday morning in Denver.

Defending Campbell is Senate Chief Counsel for Employment Jean Manning. She has argued in briefs that the Wyoming judge (who decided the case after all of the district judges in Denver recused themselves due to their acquaintance with the Senator) correctly determined that Bastien’s case couldn’t proceed “without asserting questions about acts that are part of the legitimate, legislative function of Congress and the motivation for those acts, thus threatening and interfering with the independence of a legislator.”

The protected legislative activity “includes the authority to reorganize and fire, without judicial interference,” Manning wrote. “If this action were to proceed, the Court would be forced to impermissibly inquire into matters essential to the legislative process and the Senator’s legislative agenda such as the nature and purpose of plaintiff’s meetings with constituents, how the information obtained from these meetings impacted Senator Campbell’s legislative agenda and activities, and whether plaintiff’s performance of her job duties frustrated that agenda or misguided the Senator as to the will of his constituents. That is precisely the type of judicial intrusion the Speech or Debate Clause prohibits.”

While Jones Day attorney Traci Lovitt will argue the larger constitutional questions, Bastien’s lawyers, Evangelisti and Karen Larson, will speak to the factual record. The two plan to argue that even if the district court was correct in determining that Speech or Debate does provide some kind of immunity, the record in this case did not justify a dismissal.

Evangelisti maintains that the district court erred in letting Manning mischaracterize his client’s job duties, which led the judge to incorrectly conclude that Bastien was deeply involved in the legislative process. Bastien, who was employed by Campbell for seven years before being fired at age 62 and worked on immigration matters for the Senator’s constituents, was far less involved in the legislative process than the district court assumed, he said.

“The judge said the duties were legislative, but the Senators’ office has never said why she was terminated,” Evangelisti added. “Let’s say she was terminated because she was a woman, then what the hell does that have to do with Speech or Debate?”

More broadly, Nager said the amici will assert that “Speech or Debate has no application to employment actions, and thus the district court erred in engaging in any Speech or Debate Clause analysis.”

Campbell’s Senatorial duties would not be impaired by letting the case go forward, the lawyers have argued. “In a CAA case such as this one, no one is asking for a court to assume a legislative function. Whatever the outcome of this case, Senator Campbell will remain free to perform his legislative functions without judicial interference. Senator Campbell will remain free to vote on legislation, propose legislation, hold hearings, and participate in the legislative process,” Evangelisti wrote.

In her complaint, Bastien contends that she was subjected to an “intimidating and hostile” workplace and suddenly dismissed because of her age, both overseen by Campbell Chief of Staff Ginnie Kontnik, who was “known by staff members to be manipulative and cruel to older staff members, discriminatory against older workers and verbally disrespectful to Senator Campbell, his family and older workers.” Kontnik recently left Campbell’s office amid allegations that she demanded a kickback from an underling with the Senator’s tacit approval.

Citing health concerns, Campbell announced earlier this month that he would not seek re-election.