There have been significant changes in state laws over the past few years that regulate the use of marijuana, but that hasn't made the question of whether or not to accept underwriting from dispensaries any less thorny.
The question comes down to a conflict between state and federal law.
Last year Greater Public’s legal counsel for communications, John Crigler of Garvey Schubert Barer, put it like this:
“[On] August 29, 2013... the Department of Justice issued new guidelines on marijuana enforcement policies. Here’s the dilemma. Marijuana dispensaries are now legal for medical purposes in more than 20 states and, as of 2016, marijuana is legal for recreational use in seven states and the District of Columbia. However, under the Comprehensive Drug Abuse Prevention and Control Act (a federal law popularly known as the Controlled Substances Act), it is a crime to manufacture, distribute or even possess any controlled substance, including marijuana." (Read the rest of John Crigler's article here.)
It is thus unclear if the First Amendment would protect the underwriting message in question, since “advertisements” - and, it could be argued, especially underwriting messages - are protected by the First Amendment only if related to "lawful activity."
And this is reason enough to not accept underwriting from marijuana dispensaries or any other marijuana related business.
So has anything changed?
Over the past two years, the number of states with laws that broadly legalize marijuana in some form has gone up by 43% to include 29 states and the District of Columbia, according to an Inside Radioarticle published this month.
But the article highlighted reason to be cautious. “In Washington, D.C. the Attorney General said the government was returning to a ‘rule of law’ directing federal prosecutors to enforce all the laws related to marijuana activities.”
The upshot is: As long as state and federal laws are in conflict with each other, the safe choice is still to not accept underwriting from marijuana related businesses.