Q.A landlord lets out his premises to a tenant, knowing full well that the tenant intends to use the premises for running an illegal gambling den. Can the landlord recover the agreed rent from the tenant through a court of law?

The landlord's own knowledge of the unlawful purpose is what taints this particular letting agreement under Section 23.

Step 1 — Identify the object being examined. Section 23 looks not only at whether the AGREEMENT'S OWN TERMS are lawful (a simple lease of premises is perfectly lawful on its face), but also at whether it is entered into for an UNLAWFUL PURPOSE the other party knows of.

Step 2 — Apply Section 23's test. Section 23 makes the object of an agreement unlawful where it 'would defeat the provisions of any law,' involves 'injury to the person or property of another,' or is one the court regards as 'opposed to public policy.' A letting knowingly made to facilitate an illegal gambling operation squarely falls within this — the landlord is not a passive, unwitting party but knowingly participates in furthering an unlawful object.

Step 3 — Effect on the letting agreement. Because the object is unlawful, the agreement (for that letting, on these facts) is void under Section 23. A void agreement with an unlawful object is one the courts will not assist EITHER party to enforce. …