Legal? Tenant putting cameras in laundry room?

[Brie Schmidt]

So I have a 3 flat with 1 tenant who is just causing problems.  They are all in leases till June and he pays, so nothing I can do.  But for the last 6 weeks it has been one thing after another and recently he thinks someone stole his laundry from the laundry room. So I talked to everyone and did set laundry days for each unit to solve the problem.  Today is his day and there is now a camera in the laundry room with a note that says "you are being recorded."

Putting aside the sheer pettiness of this drama - is this legal?  The laundry room is off the first floor unit at their back door.  They are concerned specifically if it records audio, which is a valid concern.  I am obviously going to talk to him about it but wanted to know my position first.

This is Chicago so do you know @Mark Ainley @Bob Floss II