At least two towns have decided to sue the Martha’s Vineyard Commission in superior court over its recent decision to approve the Oak Bluffs roundabout.

On Monday Edgartown selectmen voted to appeal the commission’s controversial decision, and on Wednesday West Tisbury joined the cause, citing “a staggering amount of opposition” to the project.

Edgartown selectman and board chairman Arthur Smadbeck was the first to urge his colleagues to consider going to court to block the roundabout.

“The Martha’s Vineyard Commission recently made a decision on a plan that is not a complete plan on changing a traffic pattern,” Mr. Smadbeck said, referring to the proposal reviewed and approved by the commission — a so-called 25 per cent traffic engineering plan, still subject to design tweaks.

“Although technically it’s in Oak Bluffs, there are probably more Edgartown residents that flow across that intersection,” he added.

Selectman Margaret Serpa was wary at first.

“I think it’s unfortunate [the commission’s decision], but I don’t know what an appeal would do,” she said.

“It would get the discussion going that should have gotten going before this whole thing rushed through in the first place,” responded Mr. Smadbeck.

Selectman Michael Donaroma also hesitated but eventually agreed with the idea.

“I don’t have strong feelings one way or another on the construction of the roundabout,” he said. “I’ve heard that the plan that the commission has approved isn’t really even the plan . . . they made a decision on a plan that doesn’t really exist. That bothers me. I’m going to make a motion to appeal the decision until they get the right plan.”

The vote was unanimous.

On Tuesday Tisbury selectman Geoghan Coogan said his board would refrain from any decision on the appeal until selectman Tristan Israel returned from an absence, and while he did indicate solidarity with his fellow down-Island selectmen, he stopped short of joining the appeal.

“Edgartown has filed an appeal and it would be my thought not to jump ship with them,” he said. “Let them spend the money on the appeal. It’s going to be heard. It’s going to go to court.”

On Wednesday West Tisbury selectmen were less reluctant.

Selectman Richard Knabel, who led the move to refer the project to the commission as a development of regional impact last summer, said the roundabout represented a “radical change” to the culture of the Island.

“I and many other people are now disappointed in both the process and the outcome,” Mr. Knabel said. “The design concept that the MVC has just approved is just that. It’s a design concept; it’s not a final plan. We have no idea what the final plan is going to look like or what the final cost will be.”

Early last month a sharply divided MVC approved the traffic improvement project for the blinker intersection by a single vote. Three weeks ago an attempt by commission member Leonard Jason Jr. to reconsider the matter failed, again by a single vote.

According to commission staff documents the roundabout will cost $1.2 million and will be funded through a state surtax on gasoline earmarked for traffic projects.

This week selectman Cynthia Mitchell echoed Mr. Knabel’s sentiments.

“I thought the process was flawed, flawed and flawed and I think an appeal maybe stands the possibility of succeeding because of that,” she said. “Who was not served in this was the public.”

Ms. Mitchell was particularly irritated that the commission chairman allowed the reconsideration vote sparked by Mr. Jason to take place while one of its most ardent opponents, West Tisbury commissioner Brian Smith, was away. As he did in the first vote, chairman Chris Murphy cast the deciding vote that night.

“A key vote was missing from that room,” Ms. Mitchell said. “I was shocked . . . How could you take a vote without all the people who were originally in the room in the room. The chairman or someone in the room should have made the suggestion that that vote not be taken.”

Selectman Jeffrey (Skipper) Manter reluctantly agreed to back the challenge, but noted that the cost of the appeal would be borne by the taxpayer.

“Getting involved in a lawsuit that pits one municipal agency against another is a little uncomfortable to me,” he said. “The commission’s [legal] win-loss isn’t too bad. This isn’t going to be cheap,” he added.

“It’s going to cost you,” Ms. Mitchell concurred.

“I respect your concerns about this, but I do think that this is an important message that the MVC has to try to digest,” Mr. Knabel told Mr. Manter. “There’s two towns saying we really don’t like your decision enough that we’re willing to take this to superior court.”

When it came time to vote on the motion to appeal, Mr. Manter voted “aye” after a long pause.

“I figure it might lead to my traffic light,” he said. “I’ll get it one way or another.”