An issue many have trouble with, and many games innacurately and inappropriately deal with.
Censorship should not be encoded into the game itself, instead, players should be able to input words they find offensive so that the chat will turn the word into an asterisk.
This makes perfect sense as different people have different concepts of swearing but the absolute true one is that swearing alone are just words that nobody can reasonably take an offense to unless they are used as insults, and when that occurs, it is really the insult that is taken to offense, Not the swear word, but when an insult is uttered around them but not to them they take no offense, This is a double standard that isn't acceptable and is always wrong no matter the person, or culture.
My suggestion would allow people to put in the word ass, but be sure to only censor words they type in exactly, because other words may include parts of a "swear". Now This is the biggest part of what bothers me in other games that censor, It destroys my vocabulary because many words I use have many syllables, and some of those words include swears that are censored. Trying to pick apart my comment to find the swear really takes too much time.
This would be easier to do than a preset list of censored words aswell.