Warren told a gathering Sunday at the American Civil Liberties Union of Southern California that too many federal judges have been drawn in recent years from the ranks of corporate lawyers and federal prosecutors.

“For the courts to be a level playing field it’s critical that the judges presiding over these playing fields have the kind of knowledge and experience that helps them understand the full range of the issues they will confront,” Warren said. “They need to be the best and brightest practitioners of law in this country, drawn from every corner of the profession.”

“But if that’s the goal, we are in real trouble,” she continued. “Look closely at the composition of the federal bench today, and you’ll see a striking lack of professional diversity among the lawyers who currently serve as federal judges.”

She said President Barack Obama had nominated just 11 judges with a background in working with indigent clients, but she said his nominees had not been diverse enough.

“(Even after the filibuster rules change) nearly ¾ of president’s nominees have been lawyers who have had significant corporate law practice in the private sector, spending years representing those whose voices are already plenty loud and already heard in government,” Warren said.

“Our courts cannot provide a level playing field without judges who know what it’s like to represent a family about to lose a home because someone sold them a mortgage that was designed to explode,” she said, “or represented a teenager accused of a crime because he was walking down the wrong street on the wrong night or represented an employee tossed out of a job for saying that employees should unionize or represented a customer that got ripped off by a big company and can’t afford the cost or a court fight.”

Warren urged the civil rights activists to pressure the president and Congress to find “highly qualified judges whose professional experience extends beyond big firms, federal prosecution, and white-collar defense.”

“That’s our best hope for preventing the corporate capture of our federal courts,” she said.

But that won’t happen if Republicans sit on Obama’s judicial nominees for the next two years, as many conservatives have urged.

“They deserve up or down votes,” Warren said. “Don’t let anyone tell you the Senate can simply ignore the president’s nominees for the next two years.”

She cited Article 2, Section 2 of the Constitution, which grants the president power to nominate federal judges with the advice and consent of the Senate.

“There is no clause that says, except when the president is a Democrat,” Warren said.

Watch video from the speech posted online by ACLU of Southern California: