A Denver ABC affiliate was about make history this week by airing the first-ever marijuana TV commercial. But now the move is on hold as the station’s lawyers review it--presumably to debate the legal consequences of airing an ad for a federally-banned substance over federally-regulated airwaves.

It’s one of many strange situations for states that have legalized recreational marijuana—business owners can sell marijuana, but their ability to advertise remains severely limited. Colorado, for example, prohibits “advertising that is visible to members of the public from any street, sidewalk, park or other public place.” One shop owner was banned from even putting up a sign that said "open" with green crosses beneath it. 

This means that, on TV in particular, marijuana companies will have to tread with caution. In fact, neither of the two proposed Denver TV ads explicitly mention or depict marijuana, according to descriptions provided to The Denver Post.

The first ad, for “The Green Solution,” a dispensary company, was originally set to run on Thursday on KMGH, just ahead of Jimmy Kimmel. It portrays a series of real people—a construction worker, a purchasing manager—who then say “I shop at The Green Solution.”

A second ad, for Neos cannabis oil vape pens, says, “Neos. Recreate responsibly,” as young people participate in innocuous activities like hiking. 

Will the channel ever find its way around federal regulations? They seem to think so.

“In the old days, Mary Tyler Moore and Dick Van Dyke slept in separate beds, now we have Viagra ads. Things evolve,” KMGH vice president Brad Remington told The Denver Post.

(h/t The Cannabist)