SAN JOSE -- The South Bay movement to fast-track the opening of charter schools has been dealt a setback, with a court ruling that county school boards can't override local ordinances while deciding where to place campuses.

In a widely anticipated order, Santa Clara County Superior Court Judge Franklin Bondonno has ruled that the Santa Clara County Board of Education lacks authority to exempt charter schools from zoning rules.

The judge affirmed a tentative decision he issued last fall, when he wrote, "If the Legislature had intended to grant the power to override local zoning to county boards of education, the Legislature would have so stated. It has not done so."

The ruling could spell difficulty for 20 Rocketship charter schools approved by the Santa Clara County Board of Education. The first of the schools was scheduled to open in August.

Bondonno ruled in favor of San Jose Unified School District and Brett Bymaster, who lives near a site near the Tamien light-rail station, where Rocketship Education hopes to locate a K-5 charter school. Both sued the County Board.

"We are pleased that the court ruled on the side of the community, ensuring that decisions on school placement are made by local authorities," Bymaster said.

The order isn't intended to prevent the growth of charter schools, noted Vincent Matthews, superintendent of San Jose Unified, which filed the suit. "This lawsuit was intended to correct the County Board's exercise of a power only granted to school boards," he said.

County School Board President Leon Beauchman issued a statement, pledging to "explore all options." Denying the board the tool of zoning exemptions, he wrote, removes equity among local districts and the board, and "discriminates against charter schools based upon the authorizing body."

Rocketship Education officials also expressed disappointment. Referring to the Tamien site, which the organization purchased, "We continue to believe the site is appropriate for a school," said Rocketship Bay Area Vice-president David Kuizenga. "We're disappointed that rather than being able to focus on educating our Rocketeers and working with families, we're having to commit resources to litigation."

The San Jose City Council deadlocked on rezoning the property, so the fate of the Tamien-site school remains undetermined.

The non-profit Rocketship seeks to open schools for primarily low-income, immigrant students attending under-performing public schools.

Most charter schools -- which are publicly funded but operate independent of elected boards of education and freed from most requirements of California's voluminous Education Code -- secure their sites from the school district where they operate. But Rocketship runs on a different model, quickly erecting classrooms on vacant sites.

In a separate lawsuit, four Santa Clara County school districts are seeking to rescind the approval of the 20 Rocketship schools and prevent the county school board from granting similar requests. The suit, which hasn't yet been heard, argues that only local school districts can approve them.

Contact Sharon Noguchi at 408-271-3775. Follow her at Twitter.com/NoguchiOnK12.