At Hearing, Regulators Discuss JPMorgan Investigation Federal regulators shed new light on their investigations into JPMorgan Chase's multimillion-dollar loss, telling Congress that they were examining potential wrongdoing and weighing whether the bank's trading debacle would reshape rules for Wall Street. In a Senate Banking Committee hearing on Tuesday, the leaders of the Commodity Futures Trading Commission and Securities and Exchange Commission confirmed reports that their agencies had opened investigations into the nation's biggest bank by assets. While the C.F.T.C. is examining how JPMorgan's trading affected the market for credit derivatives, the S.E.C. is poring over the bank's public disclosures to see how forthcoming it was about the troubled trades. "Our focus is on the quality of their risk disclosure," Mary L. Schapiro, the chairwoman of the S.E.C., said at the Senate hearing on Tuesday. "We're very focused on the accuracy and timeliness of that disclosure," she said, adding that the agency will check whether the bank's first quarter financial reports were "accurate and truthful." Gary Gensler, chairman of the C.F.T.C., said he would decline to "provide any specific information about a pending investigation." But he discussed, in theory, the agency's authority to investigate fraud and manipulation of the derivatives market, the instruments at the center of JPMorgan's trading blunder. The banking committee on Tuesday began a round of hearings about JPMorgan, which disclosed this month that it had lost at least $2 billion in trading in a London unit, blaming "errors, sloppiness and bad judgment." The losses are now thought to have climbed to at least $3 billion. The committee will hold another hearing on June 6 with some of JPMorgan's main regulators, including the Federal Reserve and the Office of the Comptroller of the Currency. The C.F.T.C. and the S.E.C. did not have direct oversight of the JPMorgan unit that had placed the trades. A third hearing, scheduled for later in the summer, is expected to include testimony from Jamie Dimon, JPMorgan's chief executive. The bank's trading blowup has inspired some lawmakers and consumer advocates to ramp up calls for a regulatory crackdown on Wall Street. "The company's massive trading loss is a stark reminder of the financial crisis of 2008 and the necessity of Wall Street reform," the chairman of the committee, Senator Tim Johnson, Democrat of South Dakota, said at the hearing on Tuesday. This trading loss has been a wake-up call for many opponents of Wall Street reform. Senator Richard Shelby of Alabama, the ranking Republican member of the committee, countered that it was unwise for regulators to "micromanage what entities are doing," noting that "JPMorgan is a huge bank." Much attention has centered on the proposed Volcker Rule, which would prohibit banks from trading with their own money, or what is known as proprietary trading. Regulators are expected to complete the wording of the rule in the coming months. The two Democratic authors of the Volcker Rule - Senator Jeff Merkley of Oregon and Senator Carl Levin of Michigan - say it will prevent trading implosions like the one at JPMorgan. "The Volcker Rule is foremost in everyone's minds," Ms. Schapiro said. She acknowledged, however, that it was unclear whether the rule would have banned the JPMorgan trading. The bet began as a hedge, which is largely exempt under a draft version of the rule, though it probably evolved into a proprietary trade over time. Senator Bob Corker of Tennessee, a prominent Republican member of the committee who initiated the push for a JPMorgan hearing, wanted to know how regulators would factor the JPMorgan loss into the rule-writing process. "I think it gives us real live experience," Mr. Gensler said.