Officials at the local school district in New Orleans fired back for the first time Monday in a legal dispute with two of the independent charter schools under their watch over how to allocate tax dollars for students with special needs.

In a joint motion, the Orleans Parish School Board and the board’s superintendent, Henderson Lewis Jr., asked a federal judge to throw out a lawsuit filed last month by Lusher Charter School and Lake Forest Charter Elementary School, arguing that state court, rather than federal, is the proper venue for the case.

The 26-page filing deals mainly with whether a breach of contract the schools are alleging on the part of Lewis and the board really took place, and whether it would amount to a violation of the so-called contract clause of the U.S. Constitution, which says in part that no state can pass a law “impairing the obligations of contracts.”

Lusher and Lake Forest, two independent schools that operate according to contracts with the OPSB, said in their suit that board members “impaired” those contracts by giving Lewis discretion to adopt a new funding formula that shifts more dollars to schools with higher numbers of special-needs students.

They cited contract language spelling out that they receive tax dollars according to a formula adopted by a state education board each year.

The schools asked U.S. District Judge Jane Triche Milazzo to rule on that point immediately.

In their motion to dismiss the suit, district officials say those same contracts spell out explicitly that any dispute between the parties should take place in state court. They also say there was no impairment of the contracts to begin with, and even if there had been, it would not amount to a constitutional violation.

They argue that a contract dispute becomes a federal issue only when a state or local government “forecloses the possibility of damages or an equivalent remedy,” which they say has clearly not happened, given that Lusher and Lake Forest are asking for damages in a lawsuit.

In any case, district officials say there was no impairment to begin with, because the charter contracts in question stipulate that wherever the agreements reference federal, state or local laws, both parties will be “bound by any amendments to such laws.”

Lusher and Lake Forest base their claim to a certain funding formula on a reference in their contracts to a state law dealing with charter schools. It says charters will be funded according to the per-student formula adopted annually by the state Board of Elementary and Secondary Education. But that portion of the law was amended last year to provide for a separate formula in New Orleans — a formula that was drawn up by a local committee and eventually adopted by Lewis.

In the district’s view, the contracts signed by Lusher and Lake Forest obligate the schools to abide by the amended statute.

The district’s filing also rejects the idea that a separate formula for New Orleans violates the constitutional guarantee of equal protection under the law, citing a precedent for allowing states to differentiate among municipalities “accord to population.” The Legislature’s amendment last year did not specify New Orleans but rather any parish with more than 300,000 people.

James Brown, an attorney for Lusher and Lake Forest, said his camp was reviewing the district’s motion and “will respond appropriately.”

Oral arguments in the case have been scheduled for June 1.