WASHINGTON (Reuters) -The U.S. Federal Reserve said on Monday it was considering major changes to its annual bank "stress tests" in light of recent legal developments, including allowing lenders to provide comment on the models it uses, in a major victory for Wall Street banks.

The Fed said it may also allow lenders to provide input on the hypothetical scenarios it uses for the annual bank health checks, and that it may also average results over two years to reduce annual volatility in how much capital banks must set aside to absorb potential losses.

The Fed created bank "stress tests" following the 2007-2009 financial crisis to assess whether big lenders could weather an economic shock. They are core to the U.S. capital regime, dictating how much cash lenders must put aside to absorb losses, and how much they can return to shareholders.

The Fed said the proposed changes were not designed to affect overall capital requirements, but followed recent court rulings that have significantly changed the framework of administrative law in recent years, the Fed said.

"The [Fed] Board analyzed the current stress test in view of the evolving legal landscape and determined to modify the test in important respects to improve its resiliency."

In June, the Supreme Court dealt a major blow to federal regulatory power by overturning a 1984 precedent that had given deference to government agencies in interpreting laws they administer. The precedent the court overturned arose from a ruling involving oil company Chevron that had called for judges to defer to reasonable federal agency interpretations of U.S. laws deemed to be ambiguous.

While the 2010 Dodd-Frank law passed following the crisis broadly requires the Fed to test banks' balance sheets, the capital adequacy analysis the Fed performs as part of tests -- the resulting capital it directs lenders to set aside -- is not mandated by law.