Later this year, California residents will be voting on Proposition 19, a measure that would legalize marijuana in the state. And, given how much controversy revolves around the issue (think of the children!), we’re bound to see plenty of ads in the run-up to the November 2 election. Thing is, you won’t be seeing ads in favor of legalization on some of the web’s most popular sites, because their parent companies are afraid of being associated with a pro-marijuana stance.

The issue has come to a head over at Reddit, which reported to its users earlier today that its parent company Condé Nast would not allow it to accept paid ads in support of Prop. 19. Redditors predictably rebelled, voting up numerous stories in favor of the law (see screenshot below). And now, in a daring move, Reddit is fighting back too: it’s announced that it will begin running ads supporting Proposition 19, free of charge. Condé Nast was afraid of taking money in support of Prop. 19, so Reddit is making sure that doesn’t happen.

It’s a gutsy move. But Reddit would have faced a significant sustained backlash (and users perpetually upvoting Prop 19 stories on the site) if it bowed to Condé’s wishes. We’ve reached out to Reddit for more details and will update if we get any.

This isn’t the first time pro-marijuana ads have had issues with a popular social site. Earlier this week the Huffington Post reported that Facebook was barring ads in favor of legalization because the “image of a pot leaf is classified with all smoking products and therefore is not acceptable under our policies”. Update: This post previously said that Facebook was blocking ads in favor of Proposition 19, but the ads were for Just Say Now, an organization that’s in favor of broader legalization than just Prop 19.