20 ILCS 415/8b.3
For assessment of employees with contractual rights under a collective bargaining agreement to determine those candidates who are eligible for appointment and promotion and their relative excellence. Assessments, which are the determination of whether an individual meets the minimum qualifications as determined by the class specification of the position for which they are being considered, shall be designed to objectively eliminate those who are not qualified for the position into which they are applying and to discover the relative fitness of those who are qualified. The Director may substitute rankings, such as superior, excellent, well-qualified, and qualified, for numerical ratings and establish qualification assessments or assessment equivalents accordingly. The Department may adopt rules regarding the assessment of applicants and the appointment of qualified candidates. Adopted rules shall be interpreted to be consistent with collective bargaining agreements.
20 ILCS 415/8b.3