Petaluma will add its weight to a renewed legal battle for public access on city-owned Lafferty Ranch northeast of town.

City Council members voted 5-1 during a closed session Monday night to join a lawsuit that was filed in January in Sonoma County Superior Court.

The move became necessary after a court decision last week in which Judge Elliot Daum ruled that a private citizens group that initiated the suit did not have legal standing to fight the battle on behalf of Petaluma.

Friends of Lafferty Park, Bill Kortum, Larry Modell and other longtime advocates for a park on the 270-acre site off Sonoma Mountain Road filed suit against adjacent landowners Kimberly Pfendler and the Bettman-Tavernetti family, among others.

"We said, &‘We're citizens, we're taxpayers, that's our property too; we have standing to sue,'<TH>" said Matt Maguire of Friends of Lafferty. "But Judge Daum took a more narrow reading of the law. Nonetheless, the city and county have a lot at stake here. We're confident the county will see the wisdom of joining our suit."

Daum gave the plaintiffs 30 days to amend the suit.

The county will be asked to join the suit as well, said Petaluma Councilman Mike Healy, a lawyer who is providing free legal work to the cause.

Access to the wooded, rolling hills is a key issue.

Petaluma has owned the land since 1959 and for a time used it to provide some of the city's water. In the 1990s, disputes over public access to the site polarized Petaluma politics and sparked heated legal wrangling.

At the center of the dispute is a 905-square-foot triangular piece of land at a turn in Sonoma Mountain Road where multiple property lines converge. Just beyond it is the gate to Lafferty Ranch, the undeveloped property's sole entrance.

Adjacent property owners argued that the city property was landlocked and they blocked access. They have asserted that the grass and dirt patch between the county road and the Lafferty gate is their private property.

After years of fighting and $900,000 in studies and legal costs, in 2002 Petaluma abandoned further attempts to open the park on its own. Deals with the state and county also fell through, at least in part due to access problems.

In January, the citizens group filed a new suit, arguing that an 1877 county map shows the entire width of Sonoma Mountain Road on Lafferty Ranch. Because the county never abandoned any portion of the road easement, nor have the property lines moved, Lafferty Ranch continues to have access to Sonoma Mountain Road, the suit says.

Councilman Chris Albertson, the lone vote against joining the suit, said Tuesday he had concerns about cost and liability to the city.

"These things have always struck me as a request for a blank check. If the city is a party to this, the city shares some responsibility if it all goes against the city," he said. "We don't know where it's going to take us. If the city loses, are we going to appeal? Are we automatically on the dime for the appeal? We don't have that much money."

Healy said the private attorneys "are committed to continuing to do the lion's share of the work" as the suit moves forward.

As far back as 1962, Petaluma planned to open the land as a nature preserve available to hikers and other passive recreational uses. The tree-studded, rolling hills provide panoramic views of Petaluma, San Pablo Bay and on clear days, the Pacific Ocean.