FAIRFAX, Va. —  The nation's largest circus went on trial Monday on allegations that it ran an extensive corporate espionage campaign against an animal-rights group and hired a former CIA operative to help conduct the operation.

People for the Ethical Treatment of Animals sued Vienna, Va.-based Feld Entertainment, which produces the Ringling Bros. circus, more than four years ago, claiming the company's president supervised the spying efforts.

PETA claims circus operatives stole sensitive documents such as donor lists. It is seeking $1.8 million in legal fees and damages, as well as full disclosure of the alleged spying activities.

PETA attorney Philip Hirschkop described company President Kenneth Feld as "one of the wealthiest men in the Washington area" who "runs a billion-dollar business." Feld had fought unsuccessfully in pretrial hearings to prevent disclosure of his financial statements.

Feld's attorney said his client did nothing illegal and that PETA only filed the lawsuit to attract publicity. He also accused PETA of hypocrisy for complaining about infiltration of its ranks when PETA itself frequently uses undercover operatives to try to expose wrongdoing in animal research laboratories and slaughterhouses.

Feld "did not do anything to harm PETA," said his lawyer, Thomas Cawley. "This case makes no sense except when viewed as one of PETA's publicity attempts."

Feld sat silently through Monday's proceedings, occasionally consulting with his lawyers during jury selection and clenching his jaw during the opening statement by PETA's attorney.

The PETA attorney also alluded to the involvement of Clair George, the CIA's former covert operations director who was convicted of perjury in the Iran-Contra scandal but later pardoned by President George H.W. Bush.

George acknowledged in an unrelated case that he did consulting work for Feld and helped oversee surveillance of animal-rights groups.

Cawley told the jury that the vast majority of George's work for Feld had nothing to do with surveillance of animal-rights groups.

Norfolk-based PETA also said that Feld and his lawyers improperly impeded the lawsuit, which was filed in May 2001 but proceeded at a snail's pace.

In August, the judge sanctioned six of Feld's lawyers for contempt of court and interfering with a deposition. In December, a judge issued sanctions against Feld for failing to turn over evidence.

The trial is expected to last up to two weeks.