Two big banks sued over shoddy mortgage securitiesA U.S. credit union regulator has filed a lawsuit against two major banks over shoddy mortgage securities they sold during the run-up to the financial meltdown. In the lawsuit, the National Credit Union Administration (NCUA) claims U.S. Bank and Bank of America broke state and federal laws by failing their duties as trustees for 99 residential mortgage-backed securities trusts, according to Reuters.