A majority of the bank customers (52 percent) who paid a debit card overdraft penalty fee in the last year, did not recall signing up for this service and were not aware that a fee was involved, according to a recent survey by the Pew Charitable Trusts.

Why all the confusion? Is it something the banks are doing?

Four nonprofit organizations teamed up to find out. The California Reinvestment Coalition of Oakland, New Economy Project of N.Y., Reinvestment Partners of Durham, N.C. and Woodstock Institute of Chicago, sent secret shoppers into dozens of bank branches in their cities.

Those mystery shoppers, who made a total of 64 visits, received information that was often "unclear and incorrect," according to a recently released report.

"There wasn't a single bank in which every one of our secret shoppers came back with the same understanding of how their overdraft protection policies worked," said Courtney Eccles, policy director at the Woodstock Institute.

"No one understands overdraft, not even the bankers," said Andrea Luquetta with the California Reinvestment Coalition. "Many of our testers got lengthy explanations that were confusing and sometimes conflicted with the written materials they received."

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