Attorney for landowners challenging Fairfax County's ordinance sharply limiting future office development argued in court yesterday that the law is flawed by eight clerical errors made when it was drafted.

The ordinance, enacted by the County Board of Supervisors in December, is intended to cut by as much as half the amount of development allowed on more than 14,000 acres zoned industrial and commercial.

Because of the mistakes in drafting, cited in Fairfax Circuit Court yesterday as attorneys argued preliminary motions in pending lawsuits, instead of deleting offices in one district, the ordinance cut out automobile storage yards. In another district, the change deleted motor freight terminals and in a third, "establishments for the production of materials" were cut.

"Whoever drafted the resolution for the board to enact, didn't realize that the numbers {referring to certain details} had changed," said Langhorne Keith, a member of a team of attorneys for landowners in 269 lawsuits challenging the downzoning ordinance.

The county's attorneys have argued that the court should take into consideration the supervisors' intention and overlook clerical mistakes.

"It was simply a clerical error in implementing the board's enactment," said Mahlon G. Funk Jr., one of five attorneys representing the county. "The board made no errors here."

At stake in the pending lawsuits is hundreds of millions of dollars landowners say they stand to lose if the county's law to slow development is upheld. The landowners contend that their constitutional rights were violated when the county denied them the right to build office space.

In the third day of pretrial hearings yesterday, Circuit Court Judge William G. Plummer questioned the wording of the ordinance as it was introduced into evidence.

"I would feel like a fool ruling on something now and find out later it was not the ordinance," Plummer told the attorneys. "What is the animal we're dealing with? Let's find out what they passed." Plummer may rule on the issue of clerical errors Monday.

The drafting mistakes in the ordinance were brought to the county's attention by Phil Yates, a planner who worked in an engineering firm. Yates was trying to make sense of a copy of the zoning ordinance when he noticed the numbers were off. His copy of the amendment said "delete number 11," Keith explained. "What should have been deleted was number 12," which meant cutting out offices. Yates informed the county. "That's the first time the county realized they had done it wrong," Keith said.

The ordinance with the wrong numbers and letters was admitted into court as evidence on Feb. 5. A week later, the judge received a memo from a county clerk, pointing out the mistakes and asking the judge to substitute two pages "to accurately reflect the intentions of the board."