Brown's suit says her firm charges up to $4,700 per client, offers "a bevy of false promises" but usually does little on customers' behalf. Barely 10 percent of her clients have their Internal Revenue Service debts resolved successfully, the suit says.

And when unsatisfied customers want their money back, the firm hauls out phony billing statements to "systematically cheat their clients out of refunds by exaggerating the amount of time spent on their matters," the suit says.

Calls to Deutch's office in suburban Sacramento Monday went unreturned.

Brown's lawyers on Wednesday will go to Sacramento Superior Court seeking a preliminary injunction that would shut off Deutch's TV ads.

In one of her commercials, three clients talk about having thousands of dollars in IRS debts wiped off the books. In reality, Brown's suit contends, their debts were put on temporary hold, with interest and penalties continuing to pile up.

Deutch portrays herself in her ads as a no-nonsense defender of the little guy against the feds. She's written a book, "The Tax Lady's Guide to Beating the IRS," and has been interviewed on CNN, NBC's "Today Show" and other national media outlets, dispensing tax advice.

Deutch also has created a chain of tax-preparation centers in 21 states, named after her but operated by franchisees. "I want 1,000 stores! I want to be H&R Block huge!" she said in a 2007 interview with The Sacramento Bee.

One former franchisee in the Sacramento area, Gary Starbuck, defended Deutch in an interview Monday.

"She's the hardest-working woman I've ever met," he said.

Brown says Deutch's law firm does at least $25 million a year in revenue. Its assets include a $3 million annual advertising budget and a 45-employee telephone sales force.

"Of course, they have great commercials," said Rocklin, Calif., resident Sherry Williams, who called Deutch's toll-free number three years ago when she owed the IRS about $40,000.

Williams told The Bee she gave the Deutch firm a $280 down payment to resolve her tax problems. But whenever she called for an update, she said, she was unable to reach a lawyer.

Williams said she terminated her agreement with Deutch's firm and "got a real lawyer." She later filed for bankruptcy protection.

Merritt Potter, of Sacramento, said she paid thousands of dollars to Deutch's firm to clear up a $38,000 IRS bill.

"They kept saying they were working with the IRS," she said. But later, she said, she was told by the IRS that it hadn't been contacted on her behalf by Deutch's firm.

According to Brown's lawsuit, the Deutch firm typically does little for its clients beyond sending the IRS a form saying it has power of attorney.

It's not the first time Deutch has run into legal problems.

In 2006 she paid $300,000 to settle a lawsuit filed by the New York City Department of Consumer Affairs over her advertising. Deutch later told The Bee she believed the lawsuit was groundless but her lawyers persuaded her to pay "what I thought was a small amount of money to resolve it."

Legal problems also touched her Roni Deutch Tax Center chain of franchises, which has 65 outlets, including nine in the Sacramento area.

The tax-preparation business created an alliance with Money Mart, a Canadian payday lender, which was sued in 2007 by the city of San Francisco over its loan practices. The suit is still pending.

Deutch's tax-preparation arm was a Kings corporate partner last season. It ran ads during games featuring Deutch, standing on the Arco Arena floor and promising to "find your hidden tax deductions."

During a game in March, the business set up a booth outside Arco offering free tax preparation to the first 200 customers.

The tax preparation business is not included in the state's lawsuit.