The Miccosukee Tribe has turned against its former chairman with a vengeance, accusing Billy Cypress in a new lawsuit of stealing $26 million from the tribe to spend on numerous gambling trips, shopping sprees, real-estate investments and luxury cars.

Cypress, who was voted out as chairman in late 2009, is accused of conspiring with two former Miccosukee financial officers, two former U.S. attorneys and a Miami brokerage firm to keep the tribe in the dark about his alleged “criminal enterprise.”

“Consequently, the Miccosukee Tribe and the Miccosukee people were unable to discover this massive web of financial theft, embezzlement and fraud until 2010,” the federal racketeering suit claims.

The West Miami-Dade tribe’s airing of its own dirty laundry, especially in light of a separate Internal Revenue Service civil probe of its in-house gambling distributions to Cypress and some 600 other Miccosukee members, is unprecedented.

The suit, filed in Miami federal court over the weekend, details a total of $11.5 million in ATM withdrawals by Cypress at casinos in Las Vegas and elsewhere, along with an additional $4 million in American Express charges for jewelry, restaurants and other expenses, between 2006 and 2009. Cypress also acquired nearly a dozen properties and residences, from Miami-Dade to Panama City Beach, worth a total of $4 million.

For decades, the Miccosukee Tribe has kept its own business to itself, asserting its sovereign authority in countless civil and criminal legal cases, from Everglades environmental disputes to DUI-manslaughter prosecutions. But the ouster of Cypress, who was replaced by Colley Billie during a severe recession, has led to an era of fierce political infighting among the Miccosukee leadership in the public arena.

In the suit, the Miccosukee Tribe has portrayed Cypress, who served as chairman from 1987 to 2009, as a serial “thief” provided “protection” by a coterie of exorbitantly paid professionals who never alerted other tribal members about his “misappropriations.”

Among the named defendants: Dexter Lehtinen and Guy Lewis, former U.S. attorneys in Miami, whose law firms were respectively paid $50 million and $10 million for a variety of tribal services; former senior Miccosukee financial officers Miguel Hernandez and Julio Martinez; and Morgan Stanley Smith Barney, the brokerage firm that held the tribe’s various financial accounts.

On Tuesday, some of the defendants countered that the new chairman and his supporters have gone to extraordinary lengths to malign Cypress to cover up their own incompetence.

“My involvement in this suit illustrates the rash irresponsibility of the Miccosukee Tribe in always blaming someone else for their problems, instead of themselves,” said Lehtinen, who represented the tribe from early 1992 until his firing in May 2010.

Lehtinen, husband of Republican congresswoman Ileana Ros-Lehtinen, has been sued not only in this racketeering case but also in an earlier Miccosukee suit alleging legal malpractice.

“I am not aware of what was paid for with tribal funds, whether for houses, credit card purchases, or otherwise,” he added.

“I was not supposed to be aware of such matters. Tribal members themselves would have had far greater access to tribal financial records.”