Complex sentence: In April 2003, he led the indictment of Frank Quattrone who, it was alleged, urged subordinates in 2000 to destroy evidence sought by investigators looking into his investment banking practices at Credit Suisse First Boston.
Split into simpler sentences: In April 2003, he led the indictment of Frank Quattrone. It was alleged that in 2000, he urged subordinates to destroy evidence sought by investigators looking into his investment banking practices at Credit Suisse First Boston.