States across the country are legalizing medical cannabis, and patients are using it to treat dozens of different disorders–from mild anxiety, to seizure disorders, to Parkinson’s to Post Traumatic Stress Disorder. Still, cannabis is in a legal “gray area” as using and possessing marijuana for any purpose (including medical reasons) is illegal under federal law.

Currently, there are no laws that guarantee the freedom to smoke whenever and wherever, but we may start to see challenges to this due to the federal Fair Housing Act (FHA). The FHA forbids discrimination of tenants because of a disability. Medical marijuana patients who prefer or require inhalation to other methods of administration may begin to challenge anti-smoking laws that force them to choose between housing and their medicine.

So what’s a landlord to do? The medical cannabis market is growing rapidly, making this an opportunity for landlords. Properties that allow smoking are already in short supply, and The Fair Housing Act could be amended any day to include medical cannabis patients. Landlords could gain a competitive edge by not only allowing medical cannabis smokers, but by investing in house filtration systems (which run about $600) to accommodate them while protecting their property. If you are absolutely opposed to allowing smokers, just make sure you include a detailed no-smoking policy in your rental agreement.