(765 ILCS 705/15)
    Sec. 15. Changing or rekeying of the dwelling unit lock.
    (a) A lessor of a dwelling unit shall comply with the provisions of this Section regarding the changing or rekeying of the dwelling unit lock. For the purposes of this Section, "dwelling unit" means a room or suite of rooms used for human habitation and for which a lessor and a lessee have a written lease agreement.
    (b) After a dwelling unit has been vacated and on or before the day that a new lessee takes possession of the dwelling unit, the lessor shall change or rekey the immediate access to the lessee's individual dwelling unit. For the purposes of this Section, "change or rekey" means:
        (1) replacing the lock;
        (2) replacing the locking or cylinder mechanism in
    
the lock so that a different key is used to unlock the lock;
        (3) changing the combination on a combination or
    
digital lock;
        (4) changing an electronic lock so that the means or
    
method of unlocking the lock is changed from the immediately prior tenant; or
        (5) otherwise changing the means of gaining access to
    
the lessee's locked individual dwelling unit so that it is not identical to the prior lessee's means of gaining access to the lessee's locked individual dwelling unit.
    (c) If a lessor does not change or rekey the lock as required in this Section, and a theft occurs at that dwelling unit that is attributable to the lessor's failure to change or rekey the lock, the landlord is liable for any damages from the theft that occurs as a result of the lessor's failure to comply with this Section.
    (d) The provisions of this Section do not apply if the lessee has obtained the right to change or rekey the dwelling unit lock pursuant to a written lease agreement.
    (e) The provisions of this Section do not apply to (i) an apartment rental in an apartment building with 4 units or less when one of the units is occupied by the owner or (ii) the rental of a room in a private home that is owner-occupied.
    (f) This Section applies only in counties having a population of more than 3,000,000.
(Source: P.A. 97-470, eff. 1-1-12.)