If you are a community owner or manager, you should read this post:
"If you run a website, you need to follow these steps. if you don't, you're making the web, and the world, a worse place. And it's your fault. Put another way, take some goddamn responsibility for what you unleash on the world."
Source: If your website's full of assholes, it's your fault by Anil Dash at dashes.com