Answer: This is a very complicated issue on several levels. For example, marijuana is a controlled substance under Federal Law. Under Oregon law, use and cultivation in limited amounts pursuant to a lawful Medical Marijuana Card are legal. The Oregon laws are linked here. The statutes cover such things as grow-site registration; medical uses for marijuana; issuance of an identification card; and limitations on a cardholder’s immunity from criminal laws involving marijuana. For those interested, these statutes should be consulted. You have a responsibility to make sure that laws are not being violated in the community. You also have a responsibility to the rest of the other residents. Compliance with all laws is a condition of occupancy under the park’s rental agreement, its rules, and the Oregon Residential Landlord-Tenant Act. I know of no way you can honor your obligations except to ask to see the card and verify that it is current and held in the name of the resident. The main issue here is Fair Housing Laws. If the resident has a valid card, then arguably he have some medical condition that has authorized its issuance. Does he have a legal right to demand that under the Fair Housing Laws, you make a “reasonable accommodation” for his medical condition, and permit him to continue in his grow operation? Not necessarily. In January 20, 2011, the U.S. Department of Housing and Urban Development (“HUD”) issued a Memorandum, the subject of which was “Medical Use of Marijuana and Reasonable Accommodation in Federal Public and Assisted Housing.” While the Memo was limited to federal public and assisted housing, it can be regarded as a helpful – though perhaps not a “final” resource - on the issue. It is very complete and helpful for all park managers and owners. It can be downloaded at: https://www.google.com/search?q=hud%20medical%20marijuana. Here is what the Memo directs: Public housing agencies “…in states that have enacted laws legalizing the use of medical marijuana must therefore establish a standard and adopt written policy regarding whether or not to allow continued occupancy or assistance for residents who are medical marijuana users. The decision of whether or not to allow continued occupancy or assistance to medical marijuana users is the responsibility of PHAs, not of the Department.” Thus, HUD seems to be skirting the issue, leaving it up to the agency in the state that permits the use of medical marijuana. Between the lines, it appears that HUD will not enforce a fair housing reasonable accommodation claim against park ownership or management if the community has an anti-marijuana policy in place. Without such a policy, my inclination is that enforcement would be potentially riskier, since the card-holder was not aware of the limitation at the inception of the tenancy. In answer to your specific questions: • Clearly, the card has to be valid and current in Oregon. A California card, for example would not suffice. (See, State v. Berrenger, 2010). • If there is no card, or no current valid card, the growing (not use) of marijuana could be is a violation of state law. You may not be able to issue a 24-hour notice under ORS 90.396, since possession of certain amounts of marijuana pursuant to a valid card, is protected. However, you may consider issuances of a curable 30-day notice under ORS 90.630; • If others are complaining about the odor, you have an issue between enforcing the use and enjoyment provisions of your rules or ORS 90.740(4)(i) versus permitting the activity if the resident has a lawfully issued Oregon card and is not growing over the proscribed amount. In any event, I would recommend that your community institute a medical marijuana use policy as a part of your rules and regulations. See, ORS 90.610 for the law regarding rule changes. Note that the right to implement a rule change – even if it results and a material change to the tenant’s bargain with the park – is expressly permitted. In other words, you may want to proscribe ALL such activity, even if it pre-existed the new rule. Alternatively, you could grandfather in current card-holders.