~ The measure would require school districts to spend at least 65 percent of money on instruction.

JEFFERSON CITY, Mo. -- Attorney General Jay Nixon asserted Wednesday that it would be harder for him to defend the state's school funding method in court if a plan backed by Gov. Matt Blunt is enacted mandating an amount schools must spend on student instruction.

Nixon's comments came as representatives of school boards, administrators and teachers unions criticized Blunt's plan during an informal hearing held Wednesday by Democratic lawmakers.

Meanwhile, a key Republican lawmaker said he does not support a mandatory threshold for instructional spending, suggesting instead that his colleagues may be more inclined to simply make it a goal.

Blunt last month proposed a ballot measure that would require school districts to spend at least 65 percent of their money on student instruction -- defined to cover such things as teachers' salaries, textbooks, the arts and athletics, but not school librarians, counselors and administrators.

The plan also is being pushed in other states by a Washington, D.C.-based advocacy group called First Class Education.

In Missouri, the proposal would be the first addition to a new school funding law enacted earlier this year by Blunt and the Republican-led legislature. That law seeks to distribute money to schools by setting a minimum amount of spending per student. The former system relied more heavily on local property tax rates and wealth.

But a group that includes 237 of the state's 524 school districts claims in a lawsuit that the new funding law only exacerbates inequities and inequalities that existed under the previous funding method.

The attorney general's office is defending the state against the lawsuit.

Nixon expressed concern about Blunt's proposal in a letter Wednesday to the chief legislative sponsors of the new funding law, Rep. Brian Baker, R-Belton, and Sen. Charlie Shields, R-St. Joseph.

Baker said he also has concerns about requiring schools to spend 65 percent of their money on student instruction. Baker said lawmakers may try to expand the definition to include expenditure for librarians, counselors and speech therapists.

"I believe it should be a target not a mandate, and we should let the local schools districts decide how to reach that," Baker said, "and that is what most legislators feel right now. We believe in local control."

Democratic senators and representatives held an informal hearing for education groups to testify Wednesday about Blunt's plan. During the hearing, they read part of Nixon's letter out loud.

None of the school groups spoke in favor of the plan.

Scott Ciafullo, president of the Missouri Federation of Teachers and School-Related Personnel, said it was "insane" not to include nurses, counselors and bus drivers in the proposal's definition of student instruction.

"On the surface, when you look at it, the proposal sounds like a good idea for our children," he said. "In reality, nothing could be further from the truth."

Ray Patrick, executive director of the Missouri Association of Rural Education, suggested the 65 percent spending requirement for student instruction was designed to cause public schools to fail and force rural districts to consolidate. That, in turn, could harm the rural way of life, he said.

"I think you lose your community when you consolidate" schools, Patrick said.