Washington ? Credit card issuers defended their interest-rate-setting policies at a Senate hearing Tuesday as consumers told lawmakers about how sudden changes in those rates have burdened them.

A subcommittee of the Senate Committee on Homeland Security and Governmental Affairs is looking into card issuers’ hiking the interest rates of cardholders who are in compliance with terms of their cards.

Subcommittee Chairman Carl Levin, D-Mich., is aiming to pass a bill that would protect consumers from certain sudden interest rate hikes.

“When a credit card issuer promises to provide a cardholder with a specific interest rate if they meet their credit card obligations, and the cardholder holds up their end of the bargain, the credit card issuer should have to do the same,” Levin said Tuesday.

The subcommittee heard from consumers who said they were hit with whopping increases in their rates.

Freeland, Mich., native Janet Hard, for example, told senators that the rate on her Discover card jumped from 18 percent to 24 percent in February. She said a Discover representative explained to her that the company determined she was at risk of default following a spontaneous credit report it had done.

Hard told the Senate Permanent Subcommittee on Investigations Tuesday that $3,478.39 out of $5,618 in payments had gone to Discover for interest accrued over the previous two years. On a monthly level, about $176 out of her $200 payments went to finance charges. In the past year alone, Hard had paid $2,400 but reduced her debt by only about $350.

Representatives of Discover Financial Services, Capital One Financial Corp. and Bank of America Card Services defended the risk-based pricing system, which allows the companies to factor the probability of a borrower defaulting into the interest rate.

“The ability to make risk-based and default-based price adjustments to annual percentage rates (APRs) allows us to offer credit to a wider segment of the public and to price credit at a level appropriate for each borrower,” said Roger Hochschild, president and chief operating officer of Discover Financial Services.

Hard was late in paying her bill three times in one year, Hochschild told the panel.

Capital One Financial Corp. President Ryan Schneider argued it’s a matter of fiduciary responsibility to be able to modify card terms in response to changes in the economy or a consumer’s creditworthiness.

He added that congressional attempts to restrict that ability would result in a restriction on credit itself.