Gov. Baldacci put forth his plan for delivering property tax relief to the state Tuesday.

Flanked by Senate and House leaders, the governor promised new state spending for education dedicated to lowering property tax rates. He also proposed capping the property tax at 6 percent of income and expanding the circuit breaker program that provides relief to low- and middle-income homeowners.

There’s also a spending cap, which would tie the growth in local and state government spending to the rate of personal income growth.

The plan closely aligns with a proposal from the Maine State Chamber of Commerce, which is collecting signatures to put its measure on the ballot next year if the Legislature fails to pass a tax overhaul.

The governor has not released the actual legislation that would enact his proposals, and while there are good elements to the plan – especially the expansion of proven programs like the circuit breaker and the idea of low-cost loans that would help homeowners delay tax payments until they realize the profits from soaring property values – there are substantial questions that must be answered.

First, just how many Mainers currently pay more than 6 percent of their annual income in property taxes and why is that number significant? What’s magic about 6 percent? Property taxes are designed to tax the value of property. With this change, property taxes could become an extension of state income taxes, which already amount to as much as 8.5 percent.

Baldacci also proposed a constitutional amendment that would allow localities to freeze home values until property is sold or transferred. Such a change would put newcomers to the state or people who decide to move at a tax disadvantage. Neighbors with identical houses could pay very different tax rates, and that would likely make the real estate market less efficient. There would be a disincentive for people to move for a new job, or to adjust to changing life circumstances. Newlyweds, large families and retired couples have different housing needs. This tax policy could lock them into a house, even when it’s a poor fit.

Baldacci’s plan is bold. It would crimp spending by towns and cities, school districts and the state. Significant questions linger, including how to pay for the added expenditures which would approach $250 million in the first two years just for education spending.

Now the issue is in the hands of the Legislature, which must act to pass tax reform as its top priority.