FORT LAUDERDALE Nen& 0 OP Judge says he will approve deposition by Ponzi figure to Convicted Investment scam operator Scott Rothstein soon could be facing a lengthy interrogation under oath. BY PETER FRANCESCHINA Sun Sentinel Ponzi schemer Scott Rothstein, the maestro who orchestrated Florida's largest investment fraud, may soon be sitting down across from a phalanx of lawyers to face a lengthy grilling under oath. No one knows what Rothstein might want to say, or whether he would invoke his Fifth Amend- ment right against self-incrimina- tion, but a federal judge on Mon- day said he will give the go-ahead for bank uptcy lawyers and attor- neys for Rothstein's bilked inves- tors to take the locked-up fraud- ster's deposition. If Rothstein wants any hope of freedom one day, it may be in his best interest to tell all ALREADY COOPERATING He already has been cooper- ating with federal agents and prosecutors investigating his $1.4 billion fraud, and helping creditors and investors could also go toward reducing his 50-year prison term. The move by attorneys repre- senting investors and those mar- shalling assets for his defunct Rothstein Rosenfeldt Adler law firm to put Rothstein under oath comes a year and half after the fraud scheme imploded, and with a looming deadline to file bank- ruptcy clawback claims against those who profited. Rothstein, 48, is locked up ill an undisclosed location, after help- ing federal agents arrest a reputed Sicilian mobster. The attorneys said all indications are that Roth- stein is in the witness protection program, possibly under another name, and that it would likely take weeks of negotiations with feder- al prosecutors and the U.S. Bu- reau of Prisons to make him available. Federal prosecutors could ob- ject to Rothstein giving a deposi- tion, the attorneys said, if his co- operation is still required to bring criminal charges against other suspects in the Ponzi scheme. The prosecutors