Commission Amends Quarantine Order to Permit Sale of Marijuana Vaporizer Devices and Newly Manufactured Marijuana Vaping Products , December 12, 2019
Retailers may sell vaping products that have been manufactured on or after December 12, 2019 and have been properly tested. Amends November 12, 2019 quarantine order.

Massachusetts laws

1 or 10 oz. You may possess 1 oz. or have 10 oz. at home

MGL c.94G. The primary marijuana possession law.
Includes who may possess marijuana, and how much.

MGL c.94C § 32L Possession of 2 ounces or less of marijuana

MGL c.94C § 32M Possession of 2 ounces or less of marijuana; drug awareness program for those under 18

Other related laws

  • MGL c.10, § 76 and § 77 Cannabis Control Board and Advisory Board
  • MGL c.64N Marijuana tax
  • MGL c.94C Controlled substances act. 
    Includes penalties for other drugs, trafficking or possession of larger quantities of marijuana.

Massachusetts regulations

830 CMR 64N Marijuana retail taxes

935 CMR Medical and recreational marijuana regulations

Federal laws

21 USC §§ 801-971 Drug abuse prevention and control

18 USC  § 922(g)(3) prohibits any person who uses marijuana from shipping, transporting, receiving or possessing firearms or ammunition.

Selected case law

Comm. v. Cruz, 459 Mass. 459 (2011).
Police can't order a person out of a car just because they smell burned marijuana.

Commonwealth v. Gerhardt, 477 Mass. 775 (2017)
Talks about the use of field sobriety tests, and includes new Model Jury Instruction Regarding Roadside Assessments for Use in Prosecutions for Operating Under the Influence of Marijuana.

Comm. v. Keefner, 461 Mass. 507 (2012). The law which "decriminalized possession of one ounce or less of marijuana, did not repeal the offense of possession with intent to distribute marijuana, ... where the amount of marijuana possessed is one ounce or less."

Comm. v. Long, 482 Mass. 804 (2019)
"The overwhelming odor of unburnt marijuana wafting from a large, windowless, cinder-block warehouse, ... in a place where marijuana cultivation was not allowed under State law; evidence of an apparent break-in; and two isolated vehicles parked in what police officers viewed as a suspicious manner after ordinary business hours ... was sufficient to support a finding of probable cause to search a warehouse for evidence of illegal marijuana cultivation."

Comm. v. Richardson, 479 Mass. 344 (2018)
Addresses the prosecution of a person for trafficking in marijuana where that person was legally permitted to grow marijuana for medical purposes. Includes new model jury instructions

Comm. v. Rodriguez, 472 Mass. 767 (2015). The smell of burned marijuana isn't enough for police to stop a vehicle.


A running list of recreational marijuana dispensaries in Massachusetts - and those soon to open,
Provides information on dispensaries, including locations, hours, parking, and payment options.

Map view of open dispensaries

Web sources

Can my financial aid be affected by marijuana use? and other marijuana-related concerns for college students, MassLive, April 2019.
Even though recreational use is legal in Massachusetts, use by college students can cause "a major legal headache and the potential loss of financial aid if a student does not follow the law."

Cannabis Control Commission guidance documents. Includes:

Frequently asked questions about recreational marijuana, Cannabis Control Commission
Includes basic information about the Mass. recreational marijuana law, MGL c.94G.

How much marijuana can I possess if I'm over 21?

  • On your person — Up to 1 ounce of marijuana. No more than 5 grams of marijuana may be in the form of marijuana concentrate.
  • In your home — Up to 10 ounces of marijuana and any marijuana produced by plants cultivated on the premises

Marijuana in Massachusetts - what’s legal?, Dept. of Health
Handy brief list of limits, but without citations to the law

Marijuana retail taxes, Dept. of Revenue
Learn how to request a Certificate of Good Standing to complete the license registration process with the Cannabis Control Commission. You can also learn how to register with MassTaxConnect, file a tax return and pay taxes on the sale of adult use marijuana. File and pay other business-related taxes through MassTaxConnect, including withholding and sales tax.

Open letter to all Federal firearms licensees, Bureau of Alcohol, Tobacco, Firearms and Explosives, September 21, 2011.
"any person who uses or is addicted to marijuana, regardless of whether his or her State has passed legislation authorizing marijuana use for medicinal purposes, is an unlawful user of or addicted to a controlled substance, and is prohibited by Federal law from possessing firearms or ammunition."

State legalization of recreational marijuana: selected legal issues, Congressional Research Service, 2014
Explores the apparent conflict between federal and state drug laws in light of legalization in Colorado and Washington for small amounts of recreational marijuana

Print sources

Criminal law (Mass. practice v. 32) West Group, with supplement. Section 466.50 Act establishing a sensible state marijuana policy.

Massachusetts cannabis law manual, MCLE, 2019.

Massachusetts proof of cases, West Group. Annual edition. Section 47:2, Marijuana – possession and use by adults



Within Massachusetts only

Within Massachusetts only


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Last updated: January 2, 2020