WASHINGTON -- Bank regulators got a sense Thursday of how their lives will be slightly different now that Elizabeth Warren sits on a Senate committee overseeing their agencies.

At her first Banking, Housing and Urban Affairs Committee hearing, Warren questioned top regulators from the alphabet soup that is the nation's financial regulatory structure: the FDIC, SEC, OCC, CFPB, CFTC, Fed and Treasury.

The Democratic senator from Massachusetts had a straightforward question for them: When was the last time you took a Wall Street bank to trial? It was a harder question than it seemed.

"We do not have to bring people to trial," Thomas Curry, head of the Office of the Comptroller of the Currency, assured Warren, declaring that his agency had secured a large number of "consent orders," or settlements.

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

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

Warren turned to Elisse Walter, chair of the Securities and Exchange Commission, who said that the agency weighs how much it can extract from a bank without taking it to court against the cost of going to trial.

"I appreciate that. That's what everybody does," said Warren, a former Harvard law professor. "Can you identify the last time when you took the Wall Street banks to trial?"

"I will have to get back to you with specific information," Walter said as the audience tittered.

"There are district attorneys and United States attorneys out there every day squeezing ordinary citizens on sometimes very thin grounds and taking them to trial in order to make an example, as they put it. I'm really concerned that 'too big to fail' has become 'too big for trial,'" Warren said.

A Warren constituent, open-Internet activist Aaron Swartz, recently committed suicide after being hounded by federal prosecutors who reportedly said they wanted to "make an example" of him. Warren had met and said she admired Swartz and, after he died, expressed her concern by attending his memorial in Washington .

The financial regulators can blame, at least in part, Wall Street lobbyists (along with outgoing Treasury Secretary Tim Geithner and Senate Republicans ) for their embarrassing turn at the hearing. Warren would have been on the panel herself representing the Consumer Financial Protection Bureau, instead of a sitting senator, if her nomination to head the agency hadn't been thwarted in 2011.