BOSTON (AP) – An American Indian tribe proposing a casino on Martha’s Vineyard argued in federal court filings on Wednesday that it never waived its sovereign immunity when it reached a deal with the state for its ancestral lands despite what Gov. Deval Patrick’s administration contends in a lawsuit to block the plan.

In a series of legal briefs, the Aquinnah Wampanoag said they never could have waived their sovereign rights – including the right to establish certain types of gambling operations on their tribal lands – in their 1983 settlement with the state because they were not a federally recognized tribe at the time.

The state has argued that the tribe’s casino plan violates the 1983 agreement, which conveyed roughly 400 acres on the western tip of Martha’s Vineyard to the tribe. The agreement stipulates that the tribe would not “exercise sovereign jurisdiction” over the lands and that the state’s jurisdiction would never be “impaired or otherwise altered.”

The Aquinnah Wampanoag tribe, which has about 1,200 members who trace their lineage to the original inhabitants of Martha’s Vineyard some 10,000 years ago, did not earn federal recognition until 1987.

The 1983 agreement “was not and was never intended to be, standing alone, a contract or any other form of enforceable `agreement,”’ the tribe argued in its answer to the state’s lawsuit.

“Indeed, because the Tribe was not federally-recognized as of the date of the signing of the Memorandum of Agreement, it would have been literally and factually impossible for the Tribe, as a federally-recognized Indian tribe, to waive its sovereign immunity, or authorize the waiver of its sovereign immunity, at that time,” the tribe said in a separate legal brief seeking to dismiss a related complaint filed by the Aquinnah/Gay Head Community Association, a local taxpayer group.

The tribe proposes turning an unfinished tribal community center into a gambling hall offering high-stakes bingo and poker-style electronic games. The plan, which the tribe says would require a roughly $10 million initial investment, does not call for traditional slot machines or casino-style games such as blackjack and roulette.

The casino plan has been met with strong opposition from residents and even some tribal members who see it as incongruous with the quaint towns and soft sand beaches that have made the island off Cape Cod a preferred getaway for celebrities and other wealthy elites, including President Barack Obama and his family.