AUGUSTA, Maine – A Republican state legislator asserted Wednesday that Gov. John Baldacci’s competing tax relief question on the Nov. 4 ballot is unconstitutional and asked Maine’s attorney general to issue a legal opinion.

Rep. Thomas Murphy Jr. of Kennebunk said the proposal, which was put on the ballot during last month’s special session, could void significant portions of cost-sharing contracts that have been signed within school districts over the years.

Murphy cited state constitutional language which he said forbids the Legislature from passing laws “impairing the obligation of contracts.” The administration defended the proposal as constitutionally sound.

A citizen-initiated question on this fall’s ballot asks whether the state should have to pay 55 percent of public school costs. Supporters, led by the Maine Municipal Association, say the state made a commitment to pay that share under a 1984 law. The state currently pays 42 or 43 percent, officials say.

The Democratic governor said forcing the state to increase its subsidy all at once would cost too much, and submitted a bill calling for a competing question on the ballot.

As approved by lawmakers, it would instead raise school aid over a five-year span and expand existing property tax relief programs. A third choice on the ballot is neither of the above.

If either competing question receives a majority of votes in November, it becomes law.

There was no immediate reaction to Murphy’s letter from Attorney General Steven Rowe’s office, which said Wednesday it hadn’t received a copy.

“Any question from the Legislature we take very seriously,” said Jessica Maurer, special assistant to the attorney general.

Murphy said state law requires that school administrative districts have cost-sharing agreements for participating schools. He said the governor’s bill would void the portions of those agreements relating to essential programs and services.

“If one took the Governor’s cavalier approach to be constitutional in this example, then the Governor and the Legislature, in the future, could alter or even void all already legally contracted local agreements involving more than one municipality … ” Murphy’s letter said.

Baldacci spokesman Lee Umphrey dismissed Murphy’s as politically motivated and added that the only “cavalier” action was distributing the letter to the news media before the governor and attorney general were given copies.

“The competing question is not unconstitutional because it does not directly impact or impair the contractual relationship among municipalities participating in” a school administrative district or consolidated district, said a statement from Baldacci’s office.

A leader of the campaign to pass the initiated proposal said Murphy submitted the question on his own. But Dana Lee, president of Citizens to Reduce Local Property Taxes Statewide, said he nonetheless agrees that the competing question raises constitutional questions.

“We are aware of that problem and it is a very big problem,” said Lee.

The governor’s proposal, in Lee’s view, would limit many district agreements to a pupil-based formula, while many existing agreements take into account other factors such as property valuation.