A majority of bank executives surveyed by tax and advisory service Grant Thornton said the Dodd-Frank Act will not be as effective in detecting risk in the financial system or ending the threat of further bailouts as originally hoped.

Of the 231 bankers polled, 47% believe the reform will be ineffective while 52% said it would be somewhat effective. Just 2% believe it would be effective, and none of the bankers surveyed said it would be very effective.

Nichole Jordan, partner and sector leader at Grant Thornton, said most bankers are uncertain because many rules under Dodd-Frank have yet to be defined by regulators.

Under Dodd-Frank, the newly formed Consumer Financial Protection Bureau will oversee seven regulators beginning July 21, 2011. Those regulators are still forming hundreds of new rules as required by Dodd-Frank such as the Federal Deposit Insurance Corp.'s latest proposal on resolving failed financial institutions.

"Although some financial institutions are beginning their compliance efforts now, the success of financial reform is something to be measured over the long term," Jordan said.

According to the survey, 73% of the bankers said the CFPB would be the one provision under Dodd-Frank that would affect their business most, and 64% expect a change of their bank's regulator in the coming months, mostly due to the elimination of the Office of Thrift Supervision. More than two-thirds of the bankers surveyed belonged to small to mid-sized banks.

Jim Wells, president of Wellspring Consulting, which helps nonprofit consumer groups develop future strategies, said he could not understand the banks' criticism of the legislation.

"It continues to astound me that banks can be so publicly critical of legislation that has a sole purpose to ensure that consumers receive a 'fair deal' from the financial institutions with whom they deal," Wells said.

Despite the still uncertain future on bank and financial regulation, the regulators themselves are confident in the recent legislation.

"We want to have market discipline," Federal Reserve Chairman Ben Bernanke said before Congress in September. "We want firms to know that they can fail and keep them from taking excessive risks."

Write to Jon Prior.