The Securities and Exchange Commission, which is responsible for policing Wall Street, may need to scale back its ambitions to live within its means, according to a newly completed study that Congress ordered in response to the financial crisis.

The study by a private consulting firm recommends that the agency reorganize itself to become more efficient and effective.

But that alone may not solve the problem, the report says.

Congress may face a choice, the report says: Increase the agency’s budget, or change the SEC’s role “to fit available funding.”

“There are mission critical activities that the SEC is not performing that force it to make intelligent but hard tradeoffs,” says the report by Boston Consulting Group, which the SEC released Thursday.

The report comes at a time when the SEC is lobbying Congress to increase its budget, arguing that it needs more money to keep with expanded responsibilities.

“As the report notes, despite the growth of our responsibilities and market complexities, the SEC’s resources have not kept pace,” SEC Chairman Mary L. Schapiro said in a statement. “This capacity gap places our markets and America’s investors at risk.”

The study cost about $5 million, according to a source familiar with the matter who spoke on condition of anonymity because the SEC has not released the figure.

At a hearing Thursday, Rep. Scott Garrett (R-N.J.), chairman of a House Financial Services subcommittee, disputed what he called a “myth” that the agency has been starved for funds. He displayed a chart that he said shows the agency’s funding has increased faster than inflation since 2000.

The consultant’s report said the agency could delegate some activities to industry self-regulatory organizations.

But the report also said there are arguments against letting industry groups regulate themselves. “The most fundamental critique is that self-regulation is not real regulation at all,” the report said.

The agency has suffered from low morale, the consulting firm found.

“The persistently low levels of employee engagement at the SEC indicate the agency has an opportunity to re-energize its staff and middle managers,” the report said.

Nonetheless, the SEC is an attractive place to work, partly because of its flexibility, the report said. More than 40 percent of employees take advantage of telework options, it said.

The final version of the report differed in some respects from an earlier draft obtained by The Washington Post.

The draft called for “much deeper and broader” SEC supervision of FINRA, a self-regulatory group for securities firms that was formerly headed by Schapiro.

“In many of the regulatory areas where FINRA is active, it is increasingly becoming a single point of failure and the sole active regulator,” the draft said.

In the final version, the phrase “single point of failure” disappeared.

The final version said the SEC “should consider whether a more tailored approach to oversight [of FINRA] is warranted.”