Jan. 21–MOHEGAN — Four months after losing a bid for a Boston-area casino license, Mohegan Sun has joined a lawsuit against the Massachusetts gaming regulators who awarded the license to Wynn Resorts.

Mohegan Sun joined the City of Revere, Mass., and a union representing about 145 workers at the Suffolk Downs racetrack, entities that filed the suit in October, alleging the Massachusetts Gaming Commission “acted arbitrarily and capriciously, and abused (its) discretion,” while also ignoring provisions of Massachusetts’ gaming law.

In September, the commission voted 3-1 to award the license to Wynn, which proposed a $1.6 billion Everett project, rejecting Mohegan Sun’s $1.3 billion plan to develop a Revere site adjacent to Suffolk Downs. As promised, the racetrack closed soon after the vote.

“It’s important to realize that this isn’t our standard MO,” Mitchell Etess, the Mohegan Tribal Gaming Authority’s chief executive officer, said Wednesday in a phone interview. “We haven’t done this kind of thing before. But at the end of the day, we began to believe we were not treated fairly. We thought this was the appropriate thing to do.”

Etess said Wynn Resorts was allowed to make belated changes in the plan it submitted to the commission, a violation of the statute governing the process. Wynn has redesigned the exterior of its Everett project since winning the license.

“Even today, commissioners still don’t know what the place looks like,” Etess said. “They should have known what they approved.”

He said the suit seeks to have the awarding of the license “vacated,” and the licensing process restarted. “We’re not asking for them to give us the license,” he said. “We just want a fair process.”

In a statement Wednesday afternoon, a spokesman for the commission responded.

“The Massachusetts Gaming Commission went to great lengths to conduct an extraordinarily thorough and meticulous licensing competition that adhered strictly to an established set of well documented and highly publicized evaluation criteria. Each gaming license was awarded based solely on merit and the decision-making process was executed with unprecedented transparency,” Elaine Driscoll, director of communications, wrote. “We remain confident that this complex licensing process has been accomplished in a manner that is comprehensive, thoughtful and fair.”

A Wynn Resorts spokesman said that because the suit is against the commission, Wynn would have no comment on it.

The suit charges the commission violated Massachusetts’ open meeting law, engaged in improper communications with Wynn and failed to impose at least a dozen conditions on Wynn that are mandated by law, including those relating to environmental remediation, neighboring community obligations, labor agreements, pedestrian safety, investor suitability, audit requirements and a lottery agreement.

While potential conflicts prompted commission Chairman Stephen Crosby to recuse himself from consideration of the Greater Boston license, Etess said there were questions about the role he played.

“We have information that he was involved in meetings in the commission’s office,” Etess said.

The cities of Somerville and Boston have each filed their own suits against the commission, seeking to block the awarding of the license to Wynn.

Since losing out on the Boston license, Mohegan Sun has also failed to win casino licenses it pursued in Philadelphia and in the Catskills region of New York state. Its partner in the Philadelphia venture has sued the Pennsylvania Gaming Control Board over the Philadelphia decision. Mohegan Sun is not involved in the suit, Etess said.

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