The Federal Trade Commission today took up a case that had thwarted state authorities for years, accusing an Internet payday lender with ties to Indian tribes of illegally deceiving borrowers.

The agency is asking a federal judge in Nevada to order AMG Services of Overland Park., Kan., to stop the deceptive practices and pay back borrowers who its says got cheated.

“The defendants have deceived consumers about the cost of their loans and charged more than they said they would, said Malini Mithal, the FTC’s assistant director of financial practices. “The FTC is trying to stop this deception and get refunds for consumers.”

While the company has won arguments in state courts that it has tribal sovereign immunity, allowing it to make loans even in states that restrict or forbid payday loans, that protection doesn’t apply to the federal courts. Court records suggest the business has made more than $165 million, charging interest rates as high as 800 percent on small loans. Borrowers have complained in droves about the lender’s tactics. Law enforcement authorities have received more than 7,500 complaints about the business, the FTC says.

Among the defendants in the lawsuit is Scott Tucker, a professional race-car driver from Kansas City, Kan. Tucker became a millionaire from the payday-lending business he started more than a decade ago. When state investigators started digging into the company’s practices, Tucker came up with a plan to sell the business to three Indian tribes while continuing to run the company and to collect most of its profits, according to recent court records filed in Colorado.

The Center for Public Integrity and CBS News jointly investigated and exposed Tucker’s involvement in the tribal payday lending business in September.

A judge in Denver now says he misunderstood key evidence when he ruled that two payday lenders operating on the Internet were beyond the reach of state regulators because they had been sold to Indian tribes.

Denver District Judge Morris Hoffman says it’s now clear from the evidence that the sales were initially shams to cloak the businesses with tribal sovereign immunity. Yet in his new ruling, the judge still blocks the Colorado Attorney General from investigating the tribal entities further for violating state lending laws.

This bizarre twist in the seven-year-old case seems to allow Indian tribes to sell their sovereign immunity to businesses wanting to violate state laws. Critics dubbed this practice as “rent-a-tribe.” And today, at least 30 online payday lenders claim ties to Indian tribes.

The Colorado Attorney General contends that Scott Tucker, a Leawood, Kan., millionaire and professional race-car driver, started the lending businesses but then crafted sham deals with the Miami Tribe of Oklahoma and the Santee Sioux Tribe of Nebraska to keep states from shutting down his lucrative operation.

Earlier this month, Hoffman said that the evidence made it clear that Tucker’s initial deal with the Indian tribes was legitimate. Yet Hoffman got key facts wrong in his first ruling.

Hoffman said in that ruling that the tribes got 99 percent of the revenue from the payday lending business. In fact, the agreements gave Tucker’s business 99 percent of the revenue. Records show the business affiliated with the Miami Tribe grosses as much as $20 million a month.

Two Indian tribes making payday loans over the Internet, even in states that ban or restrict payday lending, won a court victory Tuesday when a Denver judge blocked the Colorado Attorney General from investigating them further.

The ruling is among a series of recent court decisions posing legal obstacles for states trying to enforce payday-lending laws. Courts have ruled that state regulations don’t apply to businesses owned by tribes. In recent years, a number of tribes have flouted state laws by making loans over the Internet with interest rates as high as 800 percent.

For eight years the Colorado Attorney General has been in court trying to stop businesses affiliated with the Miami tribe of Oklahoma and the Santee Sioux tribe of Nebraska from making loans online. Attorney General John Suthers argued that their claims of tribal ownership are a sham cooked up by Kansas City businessman Scott Tucker, who is better known as an endurance race-car driver.

Tucker started the business in 1998 and approached the tribes only after it came under investigation in Kansas and New York, the court found.

However, the tribes say that their ownership is legitimate. And despite the businesses’ beginnings, District Court Judge Morris Hoffman said not only did the state fail to prove tribal ownership was a sham but added that to him it is clear that the business arrangements today seem not to be shams.

“We’re very disappointed with the court’s order,” said Mike Saccone, a spokesman for the Colorado Attorney General. Attorneys for Tucker and the tribes did not comment on the ruling.

The ruling doesn’t necessarily end the investigation. While the state cannot subpoena the tribes or tribal entities, Judge Hoffman said authorities can still subpoena Tucker and his non-Indian business associates to determine if they still own and control the payday-lending business.