SHIRLEY — The School Committee voted to support the new Budget Committee — in concept — and to participate in the process.

But members expressed some reservations.

The newly formed Budget Committee is an updated version of the previous deficit group. It consists of the Board of Selectmen and two representatives each from the Finance and School committees.

Formed at the selectmen’s behest, its stated purpose is to reach consensus on a balanced budget to take to next year’s Annual Town Meeting.

But School Committee Chairman Robert Prescott questioned whether the new group’s reach might extend to micromanagement, with department heads asked to come before the new entity to “justify” their budgets.

When it comes to analyzing other departments’ budgets, “the question is how much should we participate?” he said. “The selectmen seem to want to proceed differently this year.”

But David Baumritter, who, with Prescott, represents the school board on the Budget Committee, said it was created with “good intentions” and that participation is key.

“As one of the largest departments … it’s good for us to be at the table,” he said.

But he sided with Prescott on departmental distinctions. “We do have to be careful …” he said. “If necessary, we could abstain from voting.”

Member Don Parker said interim Superintendent of Schools Malcolm Reid should be at the Budget Committee table. Noting that town administrator Kyle Keady participates as a nonvoting member of the group, Parker said he wants Reid there when the school budget comes up.

“I would insist that the superintendent be part of this,” he said.

Reid, for his part, said he can see both sides of the issue.

“In general” it sounds like a good idea,” he said. On the other hand, if a zero-based budget approach means scrutinizing every budget item, line by line, that might concern the School Committee.

The School Committee is autonomous by state law. Its budget is not subject to oversight by other town boards but ultimately must pass muster with Town Meeting voters.

The budget group has discussed using zero-based budgeting as a starting point. But it’s just an idea so far, Prescott said, adding that Finance Committee Chairman Frank Kolarik said it might not work across the board. “Departments operate differently,” he said.

“Are they (budget committee) going to make decisions on our budget?” asked member Paul Wilson. “Is that what I’m hearing?”

“I don’t think they are going to make any binding decisions,” Baumritter said. “The intent is to set a balanced budget for 2010.”

But Wilson said he’s leery of a planning process that might stray from “zero-based” into “robbing Peter to pay Paul.” For example, if the town budget is viewed as a whole, then one balancing strategy might be to dip into the budget of a department with a surplus to shore up another department that has a shortfall, he said.

Prescott said the effort has just begun and ground rules are still being set.

“There will be a lot of discussion at the Budget Committee table,” he said, “but at the end of the day,” it will boil down to splitting scarce revenue.

But Parker said it’s important to keep things in proper perspective. He favors “better communication” between the school and municipal sides of town operations.

“But,” said Parker, “it’s critical to remind folks that we are an autonomous board that must serve its constituents first. We won’t let anyone interfere with that process.”