Both sides in the legal dispute over the U.S. Department of the Interior’s failure to act on gaming agreements between the state and the Mashantucket Pequot and Mohegan tribes agree on one thing: MGM Resorts International shouldn’t be allowed to weigh in.

At stake is the federal approval the tribes need to open a casino on nontribal land in East Windsor.

In filings Monday, attorneys for the tribes and the Interior Department and its secretary, Ryan Zinke, argue that MGM Resorts, an opponent of the East Windsor project, lacks standing to intervene in the case. The Las Vegas-based operator, which is building a nearly $1 billion resort casino in Springfield, Mass., had sought intervener status in a December filing.

The state and the tribes sued Interior in November in a bid to compel the department to act on gaming amendments that specify the terms of the tribes’ exclusive revenue-sharing agreements with the state. The tribes, which share with the state the slot-machine revenue generated by their respective casinos — Foxwoods and Mohegan Sun — will similarly share gaming revenue from the East Windsor casino.

An Interior official declined to act on the amendments last September, finding that the department lacked sufficient information and that a decision may be unnecessary. The state and the tribes claimed that under federal regulations, the department's failure to act and to publish notice of the inaction conferred “deemed approved” status on the agreements.

In their brief, attorneys for Interior say the case involves interpretation of the Indian Gaming Regulatory Act, the 1988 law that governs gaming on tribal lands.

“MGM’s motion to intervene should be denied because this case is based on statutory interpretation of IGRA’s tribal-state compact review and remedial provisions,” the attorneys wrote. “MGM is a commercial gaming operator that does not have an adequate interest in this dispute to justify its intervention ...”

MGM’s claim that the East Windsor facility would harm its Springfield casino and make it more difficult to enter the Connecticut casino market is too speculative to establish standing, Interior argues.

“MGM does not belong in this case,” attorneys for the tribes stated flatly in their brief. “MGM has no standing in this case because it has failed to identify an imminent, concrete particularized injury that is either causally connected to this controversy or would be redressed by resolution of this case.”

In a separate filing, the state joined the tribes’ opposition to MGM’s motion to intervene.

The state also objected to Interior’s motion last month seeking “partial dismissal” of the lawsuit because of circumstances surrounding the Mashantuckets’ original gaming agreement with the state. The agreement, or compact, was imposed by the Interior secretary rather than negotiated between the tribe and the state as was the case with the Mohegans' agreement.

In the state’s brief, Assistant Attorney General Mark Kohler wrote that, less than a year ago, an Interior official “explicitly denoted” the two tribes’ agreements “collectively” as “compacts.”

“In a stunning about-face, the Defendants now ask this Court to adopt a hyper-technical reading of the law that would create two classes of compacts ... stripping one of key protections and safeguards otherwise afforded by IGRA and related federal regulations,” Kohler wrote. “The statutory construction urged by the Defendants places form over substance in a way that would lead to absurd results.” 

On Monday, the tribes hosted a ceremonial start to demolition work at the East Windsor casino site. No concrete timetable for construction was announced.

b.hallenbeck@theday.com