BARRINGTON — Four hundred and fifty taxpayers have filed a Superior Court lawsuit — hoping it will be allowed as a class action, on behalf of all property owners — against the town over the latest property revaluation, and local and state officials say that the sheer number of plaintiffs may make this case a first in Rhode Island.

Town Solicitor Michael A. Ursillo, who also serves as legal counsel for four other municipalities, said he has never heard of a class-action suit in Rhode Island seeking to scrap the results of a communitywide revaluation.

“There have been other challenges to tax assessments based on valuations that fail to reflect the full and fair cash value,” said William R. Landry, lawyer for the plaintiffs, “but I don’t think we’ve seen one that involves this number of plaintiffs.”

The suit, filed late last month, seeks to set aside the assessments performed by Vision Appraisal. It contends the firm’s work was characterized by “flawed assumptions, formulas and preconceived notions;” inaccurate data, arbitrary neighborhood classifications; inadequate sales data and arbitrary discrepancies in value between similarly situated properties.

“These defects,” the suit asserts, “caused wide margins and substantial over-assessments and under-assessments townwide.”

Ursillo said the town, in responding to the allegations, will “make it clear that the revaluation process was done in a correct and lawful manner.”

Members of the group Barrington for Equitable Taxation filed the suit after the Town Council rejected its demand that it throw out Vision Appraisal’s work. On two occasions, more than 800 taxpayers turned out to protest the statistical revaluation, claiming the firm’s methodology was deeply flawed and that its appraisers were not adequately trained.

State law requires that communities conduct full, house-to-house revaluations every nine years and perform statistical revaluations, based on representative property sales, at three-year intervals in between.

On Wednesday, council President June Speakman acknowledged that the revaluation wasn’t entirely satisfactory.

“The fact that 1,000 outcomes had to be changed is a sign that the [statistical appraisal] is a blunt instrument,” she said Wednesday. “The statistical revaluation is the real problem. The real villain is a state law that requires these revaluations be done every three years.”

According to Speakman, a perfect storm occurred during the latest revaluation, one that combined a highly volatile real estate market with a statistical revaluation, which looks at the sales prices of similarly situated properties.

“It’s unfortunate,” she said, “Because real estate values are jumping around, it undermines the credibility of the process.”

That said, 75 percent of the properties in Barrington saw their appraised values decline. Waterfront properties experienced the largest jumps in value, largely because of two sales, one for more than $4 million. Many taxpayers appealed their original appraisals and about 1,000 had their assessments reduced.

“I’m not saying Vision was wrong,” Speakman said. “I had many meetings with them and they struck me as competent and professional.”

Landry said that the taxpayers have filed suit individually, collectively and as members of a class of persons. The suit, he said, will go forward regardless of whether the court allows it as a class action. Landry said that there have been a couple of successful lawsuits of this type in Connecticut and New Hampshire.

The suit seeks to recover the cost of plaintiffs’ legal fees from the town. Landry wouldn’t say whether his clients will be responsible for his fees if the suit is unsuccessful.

lborg@projo.com