On February 13, 1987, Siegel pleaded guilty to one count of conspiracy to violate the securities laws and one count of tax evasion.[5] His guilty plea included an agreement to pay over US$9 million in civil penalties and forfeit $10 million more in bonuses and stock owed to him by Drexel—a sum many times greater than the illegal gains from his relationship with Boesky.[6][7] He received a sentence of two months' imprisonment and five years' probation, rather than ten years,[8] with 3,000 hours of community service.[9] The sentence was light because of his cooperation with other government investigations.[10] His involvement in criminal activities is recounted in the book Den of Thieves by Pulitzer Prize-winning author James B. Stewart.