WASHINGTON — Retailers and credit unions want Congress to fix what they see as a problem with fees charged by MasterCard and Visa, while the credit-card companies emphasized at a House hearing Thursday that congressional involvement would only hurt consumers.

Rep. Chris Cannon, R-Utah, introduced a bill last month that would require Visa and MasterCard to negotiate fees that retailers pay in order to accept plastic. If agreement couldn't be reached, a panel of judges would set the rates.

In a packed hearing before the House Judiciary Committee Antitrust Task Force, Thomas Robinson, vice president of regulations for the National Association of Convenience Stores, said the fees, known as "interchange fees," have increased dramatically in the past few years and have hurt his customers and his business.

Convenience stores paid $7.6 billion in card fees last year, Robinson said, up $1 billion from 2006 and double the industry's pre-tax profits of $3.4 billion.

Robinson, who also is president of the Robinson Oil Corp., which has 34 gas station and convenience stores in California, said the way credit-card companies and their banks set fees in the interchange system violates antitrust laws, and Congress needs to intervene.

"I cannot agree with my competitors to charge the same prices," Robinson said. "Banks, using the cover of Visa or MasterCard, agree to charge the same interchange fees. That is against the law, and something must be done."

But officials from Visa and MasterCard countered that merchants enjoy benefits when they choose to accept their cards, including increased sales from customers who do not carry cash or checks. The retailers also benefit from increased security and being able to sell goods and services without taking any credit risk.

Joshua Peirez, a chief payment system integrity officer at MasterCard, said that merchants already have the opportunity to negotiate their fees and can provide a discount for customers who want to pay cash.

Joshua Floum, Visa's general counsel, said that the fees have not gone up, but more people are using cards than in the past, so the amount of fees retailers have to pay has increased.

The interchange fee averages about 1.6 percent and depends on the merchant and type of card, he said. Visa and MasterCard set the fees, but the merchant's bank collects them as part of a larger charge for processing the transaction. The credit-card companies say they don't receive revenue from the fees.

The Government Accountability Office issued a report Thursday that found that federal agencies, such as Amtrak and the Post Office, have reported higher levels of customer satisfaction since accepting credit and debit cards and that government agencies have been able to negotiate lower interchange fees.

The report found mixed results from an effort by Australian regulators to cap interchange fees in 2003. Merchants have benefited from lower fees, the report said, but there's no evidence they have passed that benefit to consumers by lowering prices. Banks that issue cards, meanwhile, have reduced rewards and increased consumer fees, the GAO said.

Contributing: Associated Press.

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