Lake Luciana developers made good this week on promises to sue Napa County over the decision to reject a championship golf course in Pope Valley.

Lawyers for the developers accuse the Napa County Board of Supervisors of conducting an illegal hearing on the project, fraught with bias and procedural violations. The suit was filed Monday in Napa County Superior Court.

Napa County Counsel Robert Westmeyer said he is confident he can defend the county’s decision to reject the 18-hole Lake Luciana golf course proposed by developers Robert Radovan and William Criswell.

The two sides are scheduled to meet in court in February.

In June, the board rejected the Lake Luciana project in a 3-2 vote, with supervisors Diane Dillon, Brad Wagenknecht and Keith Caldwell voting against it.

Lawyers for the developers charged Dillon and Wagenknecht were biased because of their involvement with the Sierra Club, a vocal opponent of Lake Luciana.

The Sierra Club, which contended the golf course would be an inappropriate use of land zoned for agriculture and questioned other aspects of the project, represented opponents in the Lake Luciana hearing before the board.

Project proponents said the golf course plan was within county regulations and would boost the fortunes of rural Pope Valley.

Both Dillon and Wagenknecht acknowledge they played minimal roles on the Sierra Club’s local legislative committee, but they deny that their involvement in the club affected their votes.

Wagenknecht said that his work with local groups such as the Sierra Club is critical to understanding public opinion.

In the lawsuit, Wagenknecht also comes under fire for his friendship with Jim King, the former Napa County Planning Commissioner who was asked to step down in January because of his dealings with Lake Luciana developers.

King admitted he sought consulting work on Criswell and Radovan’s Aetna Springs project several years ago, but later was turned down. Lawyers for the developers charge Wagenknecht held King’s resignation against Criswell and Radovan. They assert that Wagenknecht told developers he would have a hard time voting for Lake Luciana because of it.

Wagenknecht said this is a gross mischaracterization of his conversation with developers. He adds that after decades in the Napa Valley, he has friends on both sides of every issue, making it unreasonable to recuse himself from every such vote.

The lawsuit against the county also charges that Dillon, Wagenknecht and Caldwell violated the Brown Act by discussing Lake Luciana outside of open meetings and conspiring together to vote against the project.

The supervisors deny that any discussions occurred that would have violated the Brown Act.

Caldwell, the newest supervisor on the board and the third vote in a slow-growth majority, for the most part escapes the lawsuit’s personal attacks. Dillon and Wagenknecht bear the brunt of the criticism. Both Dillon and Wagenknecht are up for re-election next year.

This marks the second lawsuit filed against Napa County this year over a land use vote by the board.

Napa County is also doing legal battle with Yountville resident Carol Vendrillo, who sued the county in July over a decision to let her neighbor reorganize his vineyard parcels and increase the development potential of the land.