70 ILCS 2605/4.27

No applicant for appointment in said classified service, or to a position named in section 4.13 of this Act, shall pay or promise to pay either directly or indirectly, any money or other valuable thing to any person whatever for or on account of his appointment, or proposed appointment, and no officer or employee in said classified service, or named in section 4.13 of this Act shall pay or promise to pay, either directly or indirectly, any money or other valuable thing, to any person whatever for or on account of his promotion or proposed promotion. Nor shall he by means of threats or coercion induce or seek to induce any one in the classified service to resign his position, or to take a leave of absence, or any one at the head of an eligible list to waive his right to certification or appointment. No employee shall be given a leave of absence while under charges, nor shall such leave be given as an alternative to a trial on charges.