Leahy, 31, had shared with me a couple of letters he received recently from Chase Bank regarding his two different Chase credit cards. Both letters arrived the same day. One said that, 'We are pleased to let you know that your revolving credit access ... has been increased to $10,300' -- a reward for Leahy being such a good credit risk. The other letter informed Leahy that, 'After careful consideration, we have decreased the credit line on ... your account to $1,000.' One reason given was that he had too little credit available on his other bank cards. Two cards, same issuer, same cardholder. If big banks had a sense of humor, I'd swear Chase was joking with Leahy. But they don't. What banks have is an unfailing instinct to shoot first and ask questions later, to give with the left hand while the right hand takes away, and to vigorously oppose all manner of parental supervision no matter how big a mess they make. A Chase spokeswoman declined to speak with me about the mixed messages to Leahy. Leahy himself wasn't as reticent. 'The cynic in me says they're just trying to push me from a card with terms that are more favorable for me to a card with terms that are more favorable for them,' he said. 'But it could also be that they're just dumb.' Whatever the reason, this is an industry that would clearly benefit from increased oversight. Dodd, chairman of the Senate Banking Committee, introduced legislation that would create a single banking regulator, relieving the Federal Reserve and the Federal Deposit Insurance Corp. of many of their bank-watching responsibilities. It also would do away with the Office of the Comptroller of the Currency and the Office of Thrift Supervision, and absorb all relevant divisions of the Treasury Department into a new Financial Institutions Regulatory Administration. 'Our proposal will replace the myriad government agencies that failed to rein in risky schemes with a single, accountable federal banking regulator,' Dodd, D-Conn., told reporters in Washington, D.C. As he pointed out, this would make the regulatory structure more efficient and prevent banks from 'shopping around' for the most lenient baby sitter. I buy that. Like similar legislation in the House, Dodd's bill would also create a Consumer Financial Protection Agency to ensure that holders of various bank loans, from credit cards to mortgages, are safeguarded from potentially abusive and deceptive industry practices. Moreover, it would allow states to impose stricter consumer-protection regulations than included in federal law. The American Bankers Association wasted no time in depicting Dodd's proposal as doing more harm than good. The bill 'would tear apart the existing regulatory structure only to create a new one that would produce conflicts among regulators, undermine the state-chartered banking system and impose extensive new regulatory burdens on those banks that had nothing to do with creating the financial crisis,' it said. The association added that it also doesn't like the notion of a Consumer Financial Protection Agency. The unceasing objections from the banking industry remind me of how my 8-year-old son starts bellyaching any time I ask him to clean his room. As he pointed out the other day, 'I'll just mess it up again!' Happily, the global economy is seldom affected by my son's inability to put his toys away. When banks misbehave, things can get a lot nastier. It's not that lawmakers want to crack down on banks because it sounds like fun (although it does). They're doing it because banks have proved themselves consistently unworthy of our trust. Northern California resident David Underwood, 75, told me about his Wells Fargo Platinum MasterCard. Several years ago, he was informed that the card's 12.5 percent interest rate would nearly double to 23.25 percent. 'I couldn't understand it,' Underwood said. 'I always pay my bills on time and seldom carry a balance.' He said he contacted the bank and was told he could have his rate lowered again, but only for a year. A year later, he went through the whole process again. 'This didn't seem like the way you should treat a loyal customer,' Underwood said. As it happens, he's also a Wells Fargo shareholder. So, Underwood said, he attended the bank's annual shareholder meeting in San Francisco this year. He stood up at the event and told his story to Chief Executive John Stumpf. 'We don't treat our customers that way,' Stumpf reportedly replied. Underwood said he was approached afterward by Kevin Rhein, executive vice president of card services and consumer lending, who told him to get in touch if his rate should ever skyrocket again. Sure enough, Underwood said he was notified last month that his rate was about to go up again to 23.25 percent. So he contacted Rhein's office, as instructed, and a bank official called him back the next day. This time he was told that there was nothing Wells could do to help him. 'They said everyone's cards were going up,' Underwood recalled. Lisa Westermann, a Wells spokeswoman, acknowledged that the majority of the bank's cardholders have seen their rates go up recently. 'It's a different business environment than it was a year ago or a few years ago,' she said. Be that as it may, Underwood has stopped using his Wells Fargo MasterCard. Now he uses a Visa card with a 10 percent interest rate from a local credit union. Underwood is no longer a loyal Wells Fargo customer, but he's still a shareholder. And as a shareholder, he's more than a little flummoxed by how he was treated. 'It doesn't make any sense to drive away your best customers,' he said. No, it doesn't. But who said this is a business that makes any sense? Lazarus can be reached at david.lazarus@latimes.com. 