I attribute this argument to the coffee shop guys as they were the catalyst.
Why did we not negotiate an explicit exclusive into this IGA? Good question, but the facts show that an exclusive was assumed by both parties as part of the facts. Why was it assumed? It was assumed because gambling was and is illegal in the Commonwealth. Based on that illegality, the only possible place for the casino to go would be a tribal casino on trust land in Middleborough.
The only place where trust land was possible and had been applied for was in Middleborough, so an exclusive was an assumed and built in part of the IGA. The Tribe was unable to go anywhere else to legally build a casino so Middleborough could justifiably rely on an assumption of exclusivity in Middleborough.
The only break in the exclusivity came when the Carcieri decision made it no longer possible for the Tribe to take the land into trust by way of the secretary--but the Tribe did not choose to cancel the contract at that point in time and committed to obtaining a Carcieri fix to proceed with the Middleborough casino. They even dodged the concept of any renegotiations as there already was the IGA in place. They continued to pay money to Middleborough. All of these facts helped to preserve the assumption of exclusivity, upon which Middleborough continued to justifiably rely.
Thus, I see the ability to argue that exclusivity was always a part of the agreement and that their going to Fall River was a breach of the IGA entitling us to the benefit of our bargain no matter where the Tribe builds. I think that this gives us a cause of action against Fall River and its mayor for tortious interference with known economic relations, and would allow us to sue Fall River for the benefit of our bargain (the 7M + infrastructure improvements). We may even have a claim against the Commonwealth for the same interference (if we can get past sovereign immunity).
All in all, I think an argument like this could get past a motion to dismiss if properly presented. I also note that any claim against Fall River first would be in Court--only the Tribe goes to arbitration.