The Senate is expected to approve this week the most significant reversal of regulatory requirements for financial services firms since the financial crisis, including a significant retrenchment of the heightened scrutiny for banks with less than $250 billion in assets that was implemented by the Dodd-Frank Act of 2010.

The bill, the Economic Growth, Regulatory Relief and Consumer Protection Act introduced by Republican Sen. Mike Crapo of Idaho, chairman of the Senate Banking Committee, has 25 co-sponsors, including 12 Democrats. It raises the threshold to $250 billion in assets from the current $50 billion for when some of the largest banks face stricter oversight, including the designation as systemically important financial institutions. Crapo’s bill would also give regulators more discretion in when to require stress tests of capital adequacy for banks with between $100 billion and $250 billion in assets in the event of another crisis.

Three of the Democrats, Sens. Heidi Heitkamp, Joe Donnelly and Jon Tester, are the top three Senate recipients of donations from commercial banks for the 2018 campaign cycle at this point, according to The Center for Responsive Politics.

Sen. Tim Kaine of Virginia, another Democrat who is a co-sponsor, told The New Republic he supports the bill because “it provides relief for small community banks and credit unions in Virginia, helps prevent further harmful consolidation in the banking industry, and strengthens consumer protections for all Americans.”

But some, including economist Paul Volcker, say the change goes too far. The bill also proposes to exempt banks with less than $10 billion in assets from the Volcker Rule, which limits banks from engaging in risky trading using insured retail deposits. Volcker supports this change, but wrote that he believes “alternative” rules are needed to ensure “small loopholes” aren’t “gamed and exploited with unfortunate consequences.”

“An increase to $250 billion would go too far,” he told said in a letter to Sen. Sherrod Brown of Ohio, ranking member of the Senate banking committee. Volcker wrote Brown that a threshold of $100 billion or lower is more appropriate.

In 2008, at the beginning of the financial crisis, 65 global banks had assets of more than $250 billion, but only six were U.S.-based — JPMorgan Chase JPM, -4.03% , Citigroup C, -3.16% , Bank of America BAC, -4.19% , Wells Fargo WFC, -4.95% , PNC Bank PNC, -3.56% and U.S. Bancorp USB, -4.93% . Those six banks received approximately $154 billion in bailouts during the crisis, according to U.S. Treasury records, compiled by ProPublica.

Thousands of U.S. and foreign banks, and other institutions like American International Group AIG, -4.96% , General Motors GM, -4.77% and Chrysler FCAU, -3.95% , received a total of $700 billion in bailout money.

Lisa Donner, executive director of Americans for Financial Reform, a progressive organization that advocates for financial reform in the United States, wrote in December that if the Crapo bill passes, 25 of the 38 largest banks — banks that were identified as so systemically important during the crisis that they needed billions in bailouts — would no longer get this “enhanced oversight.”

Together, the banks that would drop out of the scope of required oversight, wrote Donner, “account for over $3.5 trillion in banking assets, more than one-sixth of the U.S. total. They got about $47 billion in bailout funds during the crisis.”

It’s so rare for a bank with more than $250 billion in assets to be allowed to fail that it’s only happened once. On Sept. 25, 2008 Washington Mutual Bank filed bankruptcy with $300.7 billion in assets. JPMorgan Chase acquired the assets and most of the liabilities, including covered bonds and other secured debt, of Washington Mutual from the Federal Deposit Insurance Corporation.

Phil Angelides, who served as chairman of the Financial Crisis Inquiry Commission, which conducted the nation’s official inquiry into the causes of the 2008 financial crisis, also sent a letter opposing the bill to Crapo and Brown on Monday.

“The bill’s provisions to lift the asset threshold for enhanced prudential standards and supervision from $50 billion to $250 billion,” wrote Angelides, would substantially reduce oversight for institutions that were deemed “too big to fail” in 2009.

Paul Atkins, chief executive of Patomak Global Partners, LLC, a firm that advises financial services firms on regulatory issues and who led President Donald Trump’s transition team for independent financial regulatory agencies, told an audience of international bankers at a conference in Washington on Monday that rather than what was being characterized by critics and in the press as a wholesale upheaval of Dodd-Frank regulation, the proposal was a “refinement” of an “absurdly low threshold” for bank regulatory scrutiny.