WHEN Bank of America told its customers recently that it would start charging them $5 a month to use debit cards, it argued that it was forced to make that change because of regulations that altered the economics of the cards. Other banks agreed. The chief executive of JPMorgan Chase, Jamie Dimon, put the effects of the regulations this way: “If you’re a restaurant and you can’t charge for the soda, you’re going to charge more for the burger.” Both banks were responding to the Federal Reserve’s actions to limit the interchange fees banks charge stores each time a debit card is used for a purchase.

But the banks’ simplistic statements are merely an attempt to rationalize and obfuscate one of the largest illegal transfers of wealth from consumers to banks in American history.

Debit cards were developed by banks as a replacement for paper checks. When a consumer pays with a debit card instead of a check, the bank saves money. In the 1980s, Visa calculated the savings at 55 cents to $1.60 per check. The savings is much higher today. For decades, Bank of America, the founding owner and member of Visa (originally called BankAmericard) and all of the Visa and MasterCard banks, including Chase, hid the identity of their debit cards from stores by designing them to look and function like their signature authorized credit cards and by charging stores the same price for debit and credit transactions. Banks did this despite the fact that purchases made with a debit card didn’t involve a loan from the bank, posed very little fraud risk and were extravagantly profitable to banks because they eliminated the costs of processing and clearing checks.

The practice of deceiving stores and forcing them to accept overpriced debit transactions was challenged in a 1996 antitrust lawsuit against Visa and MasterCard, in which I was the lead attorney for the plaintiffs. In 2003, that resulted in a $3.4 billion settlement to stores, a court order to redesign the debit cards and a reduction in the price banks charge stores for common debit transactions — to an average of 42 cents per transaction from an average of 63 cents.