Democrats eager to see consumer champion Elizabeth Warren take Wall Street's biggest banks to task got their wish on Thursday when the newly elected Democratic senator made her debut at a Senate Banking Committee hearing.

"What I'd like to know is tell me a little bit about the last few times you've taken the biggest financial institutions on Wall Street all the way to a trial," the Massachusetts lawmaker said to applause, speaking to the federal regulators gathered for a hearing on Wall Street reform.

No witnesses spoke up.

Warren raised her eyebrows. "Anybody?" she asked.

Thomas Curry, head of the Office of the Comptroller of the Currency, spoke up: "We've actually had a fair number of consent orders. We do not have to bring people to a trial..."

"I appreciate that you say you don't have to bring them to trial," Warren said. "My question is, when did you bring them to trial?"

"We have not had to do it as a practical matter to achieve our supervisory goals," Curry said.

Warren moved on to the rest of the panel, knowing full well that none of the regulators present have brought a Wall Street bank to trial.

"I'm really concerned that 'too big to fail' has become 'too big for trial,'" Warren later said.

Warren ousted Republican Sen. Scott Brown in November in a hard-fought campaign. She was President Barack Obama's first pick in 2011 to head up the government's newly established Consumer Financial Protection Bureau, an entity the former Harvard University law professor and attorney helped create. But Republicans in Washington essentially killed her nomination, citing her record of taking on big banks and Wall Street. That opposition helped boost Warren's reputation and led Democrats nationwide to embrace her decision to run for U.S. Senate.