Defense lawyers for wealthy hedge fund operator Raj Rajaratnam are returning to a federal courtroom to try to reduce his bail on insider trading charges.

The lawyers want Judge Richard Holwell to reduce his $100 million bail to $20 million at a hearing Tuesday. Prosecutors say the Sri Lanka-born defendant should be detained because he is a risk to flee. They say he has the money and incentive to leave the U.S.

The portfolio manager for the Galleon Group hedge fund has been free on bail since his October arrest.

Prosecutors have charged 20 other people in what they call the largest hedge fund insider trading case ever brought. Seven defendants have already pleaded guilty.