Is a fee for smoking enforceable?

[Matt R.]

The lease signed by one of my inherited tenants contains a strict non-smoking policy that includes a clause citing a $200 fee per incident. I hadn't really thought about enforcing this policy until very recently, when it was determined during an inspection that the tenant had been smoking both cigarettes and marijuana indoors. The rental unit is part of a triplex I recently purchased in Columbia, MO and here is the wording from the non-smoking policy:

SMOKE-FREE PREMISES

A) Purpose. In order mitigate [1] the irritation and known adverse health effects of secondhand smoke; [2] the increased maintenance, cleaning, and redecorating costs from smoking; [3] the increased risk of fire from smoking; and [4] the higher costs of fire insurance for a building which allows smoking.

B) Definitions. [1] “Smoking” means inhaling, exhaling, burning, or carrying any lighted or heated cigar, cigarette, or pipe, or any other lighted or heated tobacco or plant product intended for inhalation, including hookahs and marijuana, whether natural or synthetic, in any manner or in any form. Smoking also includes the use of an electronic smoking device which creates an aerosol or vapor, in any manner or in any form. [2] “Electronic Smoking Device” means any product containing or delivering nicotine or any other substance intended for human consumption that can be used by a person in any manner for the purpose of inhaling vapor or aerosol from the product. The term includes any such device, whether manufactured, distributed, marketed, or sold as an e-cigarette, e-cigar, e-pipe, e-hookah, or vape pen, or under any other product name or descriptor.

C) Smoke-Free Premises. Tenant agrees and acknowledges that the Premises to be occupied by Tenant shall be designated as a smoke-free living environment. Tenant shall not smoke anywhere in, on, or within 25 feet of the Premises, nor shall Tenant permit any guests or visitors under the control of Tenant to do so. Tenants shall not litter the Premises with cigarette butts or similar debris, nor shall Tenant permit any guests or visitors under the control of Tenant to do so. The Premises are comprised of Tenant's dwelling unit, as well as any common areas, including, but not limited to entryways, patios, yards, community rooms, hallways, basement, laundry room, stairways, balconies, decks, and garage.

D) Tenant to Promote Smoke-free Policy and to Alert Landlord of Violations. Tenant shall inform Tenant’s guests of the smoke-free policy. Further, Tenant shall promptly give Landlord a written statement of any incident where tobacco or marijuana smoke, or vapor from an electronic cigarette, is migrating into the Tenant’s dwelling unit.

E) Smoking Violation. At Landlord's discretion, violations of this section may be considered a breach of the whole Lease. Alternatively, but also at Landlord's discretion, Tenant shall be assessed a $200 fine for each violation of this policy, to be considered additional rent. In all cases, Tenant acknowledges that a breach of this section shall also render Tenant liable to Landlord for the costs of repair to the Premises due to damage from smoke odors or residue.

F) Disclaimer by Landlord. Tenant acknowledges that Landlord’s adoption of this smoke-free policy and the efforts to designate the Premises as smoke-free do not in any way imply the Premises are any safer, more habitable, or improved in terms of air quality standards than any other rental Premises. Tenant acknowledges that Landlord’s ability to police, monitor, or enforce the provisions of this section is dependent in significant part on voluntary compliance by Tenant and Tenant’s guests. Landlord cannot and does not warranty or promise that the rental premises or common areas will be free from secondhand smoke or vapor. Tenants with respiratory ailments, allergies, or any other physical or mental condition relating to smoke are put on notice that Landlord does not assume any higher duty of care to enforce this section.