Kotz's criticism, contained in a report, could have ramifications for the SEC, which has lost several court battles over the years because of flaws in how it demonstrates that the benefits of a rule outweigh its costs.

"We found that the extent of quantitative discussion of cost-benefit analyses varied among rulemakings," Kotz wrote in his report. "Based on our examination of several Dodd-Frank Act rulemakings, the review found that the SEC sometimes used multiple baselines in its cost-benefit analyses that were ambiguous or internally inconsistent."

Last year, U.S. business groups successfully convinced a federal appeals court to overturn one of the SEC's Dodd-Frank rules that aimed to empower shareholders to more easily nominate directors to corporate boards.

In rejecting the rule, the court said the agency failed to properly weigh the economic consequences.

Some of the business groups, such as the U.S. Chamber of Commerce, have since raised similar concerns with other rulemakings pending before the SEC.

Congress passed the Dodd-Frank act in 2010 to more closely police financial markets and institutions after the 2007-2009 financial crisis. The legislation gives the SEC responsibility to write roughly 100 new rules.

Although the SEC is not subject to an express statutory requirement to conduct a cost-benefit analysis of its rules, other laws do require the agency to consider the effects of its rules on capital formation, competition and efficiency.

In addition, the SEC must also follow federal rulemaking procedures, such as providing the public with an opportunity to comment on its proposals.

This is the second report Kotz has issued looking at the quality of the SEC's cost-benefit analysis.

Both reports were issued after certain members of the Senate Banking Committee, including ranking Republican Richard Shelby, voiced concerns about whether regulators were adequately examining the economic impact of Dodd-Frank rules.

To determine how well the SEC is faring, Kotz's office retained Albert Kyle, a finance professor at the University of Maryland's Robert H. Smith School of Business, to help carry out the review.

Friday's report covered a sample of Dodd-Frank rulemakings, including a rule allowing shareholders a non-binding vote on compensation, several asset-backed securities rules and two proposals pertaining to the reporting of security-based swap data.

Kotz's report was critical of the agency in a number of areas.

In one instance, the report cites a memo in which former General Counsel David Becker gave his opinion that the SEC should do thorough cost-benefit analyses on rules that are not explicitly required by Congress.

Rules mandated by Congress, however, generally would not need the same level of cost-benefit research, the memo said.

The report suggested that the agency should reconsider these guidelines, or else it risks "not fulfilling the essential purposes of such analyses."

SEC management, in a written response to the report, disagreed with that point.

"We believe Professor Kyle's opinion fails to appreciate both the practical limitations on the scope of cost-benefit a regulator can conduct, and the distinct roles of Congress and administrative agencies," they said.

"We think it is entirely sensible ... for the staff to focus its attention and the commission's limited resources on matters that the commission has the authority to decide."

Kotz made other recommendations, including using a single consistent baseline in the cost-benefit analysis process and having economists provide more input.

SEC spokesman John Nester declined to comment beyond the SEC comments in the report.

(Reporting By Sarah N. Lynch; Editing by Steve Orlofsky, Gary Hill)

• A Permanent Economic Emergency