DENVER (AP) — Weed on Craigslist? It’s widely for sale in Colorado, but a bill moving through the state Legislature aims to crack down on folks who sell weed illegally using online ads.

A bill approved unanimously by the state Senate this week would create a new misdemeanor of advertising pot if the advertiser doesn’t have a license to sell pot.

It’s already a crime to sell pot without a license in Colorado, but there’s no crime of placing an advertisement for weed. That means law enforcement has a hard time going after those who skirt the law by selling marijuana by the pound online, hoping police don’t show up to see them make a black-market sale.

One more formal vote on the bill is required before it heads to the House.