The FCC

i know that the fcc has strong rules about what can be shown on cable and broadcast television. four-letter words are generally what you think of, though. But a week ago I saw a new episode of family guy (the one where lois wants to be a model-- i didn’t see it ON broadcast tv, but i’m sure it aired there) where a monkey rolls a joint and sticks it in his mouth. i also saw a tv show that aires on the bbc show a guy holding a lit joint. are there no rules against this? are there specific rules? has anyone seen that episode?