William Dudley, president of the New York Fed, insisted at a Senate hearing Friday that "our eyes are open" and regulators are fair, unbiased and rigorous in their oversight of the biggest U.S. banks. Democratic critics say the Fed's lax regulation of Wall Street banks could end up putting taxpayers on the hook again to bail them out as in the 2008 financial crisis. Warren and other members of the panel had testy exchanges with Dudley, who repeatedly defended the Fed's actions in several cases involving big banks and said it has made great progress in sharpening its oversight. Sen.