40 ILCS 5/19-101
The board of inspectors of the various houses of correction, organized under "An Act to authorize cities to establish houses of correction and farm colonies within the corporate limits and outside of the corporate limits within the same county and authorize the confinement of convicted persons therein", approved April 25, 1871 and maintained thereunder in cities having a population exceeding 150,000 inhabitants, shall have power, and it shall be its duty to create a house of correction employees' pension fund which shall consist of 6% of the salary or wages of the employee, together with an additional 2% of the salary or wages of male employees, deducted in equal monthly installments from such salaries or wages at the regular time or times of the payment thereof, and the net earnings of the commissary maintained and operated in the house of correction, together with the proceeds of the tax levy hereinafter provided. The number and compensation of all employees in such commissary and the use and disposition of all the funds thereof shall be approved by the board of trustees of such pension fund.
The word "salary" as used in this section shall mean actual salary but not to exceed the amount equal to actual salary paid to a Class A guard, as classified by the Civil Service Commission in Grade 3.
40 ILCS 5/19-101