WASHINGTON — Lawmakers this fall will consider stricter rules for credit-rating agencies amid criticism that they failed to accurately assess — or warn investors about — the risks that mortgage investments posed to financial markets.

The industry dominated by Standard & Poor's, Moody's Investors Service and Fitch Ratings could be forced to disclose conflicts of interest, and some say rating agencies should be banned from being paid by debt issuers — a key conflict in the eyes of critics.

It remains unclear, however, whether Congress will aim for a major overhaul of the industry or minor tweaks. Last year President Bush signed a bill designed to encourage the Securities and Exchange Commission to allow more competitors in the field, but Democrats may be inclined to support new regulations.

The credit-rating agencies, whose ratings are used by investors to gauge the likelihood of default of mortgage backed bonds and other forms of debt, are subject to oversight by the SEC, which has the power to designate companies as national rating organizations.

In recent weeks, House and Senate lawmakers have said they plan to examine the three main credit-rating agencies and their role in the mortgage market meltdown.

"It is clear that they told people things that turned out to be inaccurate," Rep. Barney Frank, D.-Mass., chairman of the House Financial Services Committee, said in an interview. Frank's committee plans to hold hearings, but he declined to describe what kind of actions might be needed, saying that lawmakers need to study the issue first.

Sen. Christopher Dodd, D-Conn., chairman of the Senate Banking Committee, and Sen. Richard Shelby, the committee's senior Republican, also have expressed a desire to focus on rating agency business practices.

Sean Egan, president of Egan-Jones Ratings Co., a Haverford, Pa.-based competitor to the traditional ratings agencies, said credit-rating agencies should be barred from being paid by the sellers of bonds.

"It's very simple: We need to create a system whereby the investors' and rating agencies' interests are aligned," Egan said. "Right now we have the exact opposite of that."

The agencies, meanwhile, defend their track record of analyzing the mortgage market in recent years and say they have adequate protections against conflicts.

There's nothing new about bond raters being paid by issuers, as that's been the case since the 1970s, said Claire Robinson, a Moody's senior managing director.

"The analysts are not compensated based on how many deals they rate," she said. Instead, she said, their pay is based on the quality of their analysis and the company's overall performance.

An S&P spokesman, Chris Atkins, said the payment model is accepted because it allows credit-rating agencies to provide ratings to investors free of charge.