DENVER — A civil lawsuit that began with a neighbors' dispute over garden plants and fighting dogs has ended in a judgment against the Denver-based chapter of the Anti-Defamation League — and what is believed to be the largest defamation judgment ever awarded in a Colorado trial.

On April 28, a 12-member jury in U.S. District Court here sided with the plaintiffs, William and Dorothy Quigley of Evergreen. The Quigleys had sued the Mountain States chapter of the ADL and that chapter's director, Saul Rosenthal.

The jury awarded the Quigleys damages, mostly punitive, of $10.5 million — a figure that astonished defendants and plaintiffs alike in the drawn-out and complex case.

The jury found that several public statements made in 1994 by Rosenthal on behalf of the ADL defamed the Quigleys and resulted in actual and punitive damages.

Rosenthal said the ADL would appeal the decision.

"We were shocked and very surprised at the result," Rosenthal said. "We're very surprised at the way the jury saw the evidence they did. I think the overall reaction within ADL and, from what I'm hearing, in the community, is complete disbelief that this kind of result has taken place."

Jay Horowitz, the Quigleys' attorney, said his clients were pleased with the outcome of the litigation.

"We did not expect a verdict of this size," Horowitz said.

The dispute began in late 1994 when the Quigleys, residents of Jefferson County near Evergreen, were accused by their Jewish neighbors, Mitchell and Candace Aronson, of plotting against their family for anti-Semitic reasons.

The dispute apparently began over such trivial matters as fights between their dogs and allegations of stolen ornamental plants. It intensified into an incident in which Candace Aronson believed that William Quigley intended to run over her with his car.

As the dispute grew more heated, the Aronsons began listening to cordless telephone conversations of the Quigleys, which they managed to overhear with a police scanner and later recorded.

After consulting with the ADL, the Aronsons later told area media of overhearing their neighbors tell crude anti-Semitic jokes and make comments that the Aronsons took to be threats against their family.

The Quigleys denied that the threats were ever meant to be serious. Rosenthal's comments about the Quigleys, made on behalf of the Aronsons after the Denver ADL agreed to state their case publicly, formed the basis of the Quigleys' defamation lawsuit.

Some of the comments, repeated over and over in numerous media accounts, shocked members of the Colorado Jewish community. In various conversations, the Quigleys refer to attaching images of oven doors to the Aronsons' house, of burning their children and of wishing their Jewish neighbors had been blown up in a terrorist attack in Israel.

Throughout the various twists and turns of the case, the Quigleys insisted that such comments were made in jest and never constituted genuine threats.

Over the next five years, the case would become a labyrinth of criminal charges filed and later withdrawn, civil lawsuits and counter- suits.

Other developments in various stages of the case:

*It was determined that the electronic eavesdropping used by the Aronsons was legal at the time, although soon afterward outlawed by both federal and state statutes. The only charges that the April 28 verdict did not support were those related to the ADL's alleged violation of the Federal Wiretap Act.

*William Quigley pleaded no contest to a reckless driving charge after driving his car in an allegedly menacing manner in Candace Aronson's direction.

*Jefferson County District Attorney Dave Thomas withdrew the ethnic intimidation charges he initially filed against the Quigleys and paid them an out-of-court settlement of $75,000.

*The Quigleys sued the Aronsons and the ADL for depriving them of their civil rights. The Aronsons settled for a non-cash settlement, but the ADL and the Quigleys were unable to reach an out-of-court settlement, leading to the most recent trial.

On April 28, the jury found most of the charges leveled by the ADL, based on the tapes, to be "not substantially true."