Many states, including Pennsylvania, bar payday lending because they recognize that it is predatory.

The state law alone demonstrates that. It outlaws payday lending by capping interest rates on short-term loans at a whopping 24 percent. Because of the way payday loans are structured, poor consumers who are the payday loan customer base sometimes end up paying 300 percent interest.

They take a loan, can't cover it by their next payday, then take another loan to cover it, and another, and on and on and on.

According to the Consumer Financial Protection Bureau, about 50 percent of all payday loans result in the borrower taking out 10 or more loans.

"One could readily conclude that the business model of the payday industry depends on people becoming stuck in these loans for the long term," the report said.

Payday lenders have been able to evade state bans, in some cases, by affiliating with out-of-state banks and doing business on the Internet.

When consumers who take those loans realize they can't pay them and enter the loan-after-loan spiral, they have little recourse. The fine print of the loan deals require any disputes to be settled by arbitration, and consumers agree when they take the loans not to enter any class-action litigation against the lender.

Since it was founded in 2011, the Consumer Financial Protection Bureau has filed 40 cases alleging deceptive practices in the consumer finance industry, which have resulted in $3.1 billion in awards for nearly 10 million consumers.

But Congress should provide further tools by authorizing the use of class action suits against financial predators.