A small group of shareholder advocates delivered an urgent message to top executives at JPMorgan Chase more than a year ago: the bank’s risk controls needed to be improved.


JPMorgan officials dismissed the warning from the CtW Investment Group, the advocates, who also cautioned bank officials that the company had fallen behind the risk-management practices of its peers.


Now, after disclosing a $2 billion trading loss at JPMorgan in May and watching the bank’s market value drop by more than $25 billion, those officials are expected to follow one of the group’s recommendations, strengthening the board panel that oversees risk.


Still, that will not address weaknesses that critics say undermined the power of the bank’s chief risk officer. According to two former traders at the chief investment office and outside specialists, the chief risk officer was not focused on the huge credit market bets the chief investment office made that eventually went bad.


What is more, in some cases, the chief risk officer did not review large trades by the chief investment office or properly set position limits, the former traders said.


“They got a bit too comfortable and seemed to ignore the chief investment office,” said one of the former bankers, who insisted on anonymity because the loss is under investigation by a host of regulators.


JPMorgan officials insist there was no structural flaw in risk management or setting position limits. “The chief risk officer has direct authority for the risk management of the entire firm, including oversight of the chief investment office,” said Kristin Lemkau, a spokeswoman for the bank.


But the critics maintain that having successfully navigated the financial crisis in 2008, JPMorgan’s risk officers became complacent about the danger posed by the chief investment office’s increasingly aggressive bets. In addition, while the office was profitable throughout the financial crisis, the chief risk officer was focused on problems elsewhere, including the bank’s money-losing mortgage business.


That complacency also caused JPMorgan Chase to lose ground, even as large rivals overhauled their risk management operations as a result of the crisis. The JPMorgan executives charged with judging risk were paid significantly less than their counterparts at other banks.


“There’s no doubt that there was a sense of overconfidence there,” said Michael Greenberger, a professor of law at the University of Maryland and a former regulator with the United States Commodity Futures Trading Commission.


The $2 billion loss does not threaten the overall health of JPMorgan Chase, which is still expected to report a substantial profit for the second quarter. But it is an embarrassing stumble for the bank, the nation’s biggest financial institution, and has emboldened regulators in Washington who are in the last stages of writing new rules for the entire industry.


It has also refocused attention on internal risk controls across the banking sector, despite the changes that have been made since the financial crisis.


“There have been increased efforts to improve risk controls,” Mr. Greenberger said. “But it wouldn’t surprise me if three or four months from now, there is another explosion somewhere else.”


Jamie Dimon, the bank’s chief executive, has acknowledged the trades were “sloppy” and “stupid,” but JPMorgan officials insist that nothing was fundamentally wrong with the risk-management structure or the ability of the chief risk officer to head off trades that endangered the bank.


While Mr. Dimon earned a reputation as a keen judge of risk, especially in the financial crisis, JPMorgan’s own chief risk officer earned less than some of his peers at rival financial giants. At Citigroup, for example, the chief risk officer, Brian Leach, earned $9 million in 2011, making him that company’s fourth-highest paid executive. At JPMorgan, Barry Zubrow, the chief risk officer until January and now in charge of corporate and regulatory affairs, was not among the top tier in compensation, and his pay is not disclosed. By contrast, Ina Drew, the executive who led the chief investment office, was near the top.