Medical Marijuana State Law Chart

To be effective, a state law must remove criminal penalties for patients who use, possess and grow medical marijuana with their doctors' approval or certification. A 13th state, Maryland, has established an "affirmative defense" law, which protects medical marijuana patients from jail but not arrest.

State, year enacted		How law protects patients		Documentation required		Registry		Marijuana quantity limit2
Alaska 1999		Affirmative defense provided only for those registered with the state.		Signed physician statement certifying diagnosis and that other medications were considered.		State Department of Health and Social Services		Up to 8 ounces of dried marijuana and six mature or 12 immature marijuana plants.
California 1996		Exemption from prosecution if marijuana possession or cultivation is solely for the patient's medical treatment.		Approval of a physician certifying patient's health will benefit from medical marijuana treatment.		Voluntary patient registry system; caregivers and patients are given ID cards, verified with 800 number.		For patients in possession of ID cards, up to 8 ounces.
Colorado 2000		Those carrying legal registry cards are exempt from prosecution. Others in compliance with the state law may use affirmative defense.		Patient must be diagnosed by a physician (prior to arrest) as having a debilitating condition and "advised" of possible benefits from medical marijuana.		State Department of Public Health and Environment		2 usable ounces and six plants, three of which may be mature. Patients may use affirmative defense to argue that greater amounts are medically necessary.
Hawaii 2000		Patient are exempt from prosecution if they have a registry card.		Patient's medical records or a statement signed by the patient's doctor.		State Department of Public Safety		No more than 3 usable ounces and seven plants, three of which may be mature.
Maine 1999		Patients are exempt from prosecution if they possess a "usable amount" of medical marijuana and have documentation of their medical condition or authorization from a doctor.		An authenticated copy of medical records or written documentation from a physician showing that the patient has a qualifying condition.		NA		2.5 ounces and six plants, three of which may be mature.
Montana 2004		Patients are exempt from prosecution if they have a legal registry card. If not, they may use affirmative defense.		Documentation from the patient's doctor.		State Department of Public Health and Human Services		1 usable ounce and six plants.
Nevada 2000		Patients are exempt from prosecution if they have a registry card. If not registered, they may use affirmative defense if arrested.		Must have proof of a diagnosis of a qualifying condition during the 12 months before any arrest.		Registry system operated by state Departments of Motor Vehicles and Agriculture.		1 usable ounce and seven plants, three of which may be mature. Patients may use affirmative defense to argue that greater amounts are medically necessary.
New Mexico 2007		Patients are exempt from arrest and prosecution if they have a registry card.		ID card requires written certification from practitioner.		State Department of Health; ID cards to be implemented by Oct. 1.2		"Adequate supply" to be determined by Health Department.
Oregon 1998		Patients are exempt from prosecution if they have a registry card. If not, affirmative defense may be used.		Documentation from patient's doctor.		State Department of Human Services		24 ounces of usable marijuana, six mature marijuana plants and 18 seedlings per patient jointly with his or her caregiver.
Rhode Island 2006		Patients are exempt from prosecution if they have registry card. If not, affirmative defense may be used.		Medical records and documentation from the patient's doctor.		State Department of Health		2.5 usable ounces and 12 plants.
Vermont 2004		Patients are exempt from arrest and prosecution if they have a legal registry card.		A signed statement by the patient, along with medical records. The patient's doctor then is contacted to verify the diagnosis of qualifying condition.		State Department of Public Safety		2 usable ounces and three plants, one of which may be mature.
Washington 1996		Patients are exempt from prosecution if they meet all criteria as qualifying patients and have no more marijuana than necessary for their personal medical use. Patients must present valid documentation to law enforcement officers who question medical use. Affirmative defense may be used by anyone arrested while in compliance with state law.		Statement signed by patient's doctor or a copy of the patient's medical records.		NA		A "60-day supply" is allowed.
The Washington State Medical Marijuana Initiative, RCW 69.51A. July 22, 2007 Amendments Amendments Effective July 27, 2007 Click here for 69.51 amendments
1 = amount that someone with a permit can legally possess; 2 = health department will issue temporary certificate from July to October Source: Marijuana Policy Project