725 ILCS 205/3.01

The proceedings under this Act shall be civil in nature, however, the burden of proof required to commit a defendant to confinement as a sexually dangerous person shall be the standard of proof required in a criminal proceedings of proof beyond a reasonable doubt. The provisions of the Civil Practice Law, and all existing and future amendments of that Law and modifications thereof and the Supreme Court Rules now or hereafter adopted in relation to that Law shall apply to all proceedings hereunder except as otherwise provided in this Act.