AUGUSTA – A crowd filled a legislative committee room as supporters and opponents squared off Monday on a bill to let Peaks Island secede from Portland.

Supporters said that without secession, the unique character of Peaks Island will disappear. Critics characterized it simply as a tax revolt.

The Maine Legislature’s State and Local Government Committee had to open up more space for the overflow crowd at Monday’s public hearing.

Robert O’Brien, whose taxes tripled after a property revaluation, said the political structure in Maine’s largest city is geared toward the mainland, leaving island residents without adequate representation.

“We’re always going to be at a disadvantage, and if a Portland city councilor has to decide between what’s best for the island or the city of Portland, they’re always going to go with the city of Portland,” he told WMTW-TV.

Not all islanders support secession, though.

“We can form a cohesive unified Peaks Island community and have a greater voice in the city of Portland,” said Ellen Mahoney. “I don’t necessarily think we have to take the extreme measure of seceding to make that happen.”

Twelve years ago, Peaks Islanders tried to separate from Portland, but legislative authorization failed by a single vote in the Maine Senate.

Since then, Chebeague Island won its independence from Cumberland last year when Gov. John Baldacci signed legislation allowing that split.

But Chebeague and the town of Cumberland presented a united front before the Legislature. In Portland, the City Council voted 9-0 against letting Peaks Island secede.

If approved, the Peaks Island bill would authorize a second vote of islanders and force Portland to negotiate a settlement with islanders before an arbitrator. In an advisory vote last spring, secession was approved by 57.5 percent of Peaks voters.

Peaks Islanders were warned that secession would likely mean higher taxes. Supporters said that was OK as long as they had a say in where the tax dollars were spent.