Legal Question in Legal Ethics in Illinois

Insufficient facts. Leases for a year or less can be oral (not in writing). Proving it up is another thing. In Chicago you may be governed by the Chicago Residential Landlord & Tenant Ordinance. It all depends on whether the tenancy can be proven. If you are the landlord you will want to try to relet asap and then you may decide whether to sue for the month+++ of rent you lose in the meantime. If you are the shy tenant you may wind up having the landlord come after you, but unless you gave checks, etc. to "seal the deal" and the landlord didn't give you the keys, there's little to prove up. Unfortunately, I know enough to say never say never....