Creating a separate topic for this to avoid clogging up the Ratings thread.
Howto:rate states that legal drug use falls under General while hard and illegal drug use falls under Sensitive. Marijuana seems to fall somewhere in the middle since it's legal in some areas but not others. For example, in the United States, it's still illegal on a federal level, but multiple states have legalized or at least decriminalized it, and the federal government is apparently fairly lax when it comes to enforcing federal laws pertaining to marijuana in those states. I mention the U.S. specifically because I'm pretty sure we're still trying to secure a payment processor and need to try to stay on their good side, and I wouldn't expect them to approve of depictions of marijuana use even if it's becoming increasingly more legal.
I wouldn't be surprised if marijuana becomes fully legalized in the U.S. in the next few years and makes this entire topic moot, but I want to focus on the present. Given the current legal status of marijuana, should we rate images showing its use as G or S? How should we treat images that only show the leaf? Should we take into account whether someone looks stoned or not?
Finally, even if these all qualify for G, should we start filtering marijuana and related tags on donmai.moe? I checked and they're still searchable (so is cocaine for that matter).