User ban system

[ag_47]

I'm working on a website, where users will be able to create posts (or blogs, or something in that manner) and participate in discussions. I am trying to create an efficient flagging system, and would like some advice.
All posts/blogs will have a report/flag button. 3 flags and the post will be automatically removed and the user/email warned. 3 warnings and the email gets banned.

Since they might as well register with a new email, I'm also considering tracking their ip. 3 banned emails from would result in an ip ban to disallow the user for good. But, since many people have dynamic ip, or an ip might get re-assigned to another person, this doesn't seem very reasonable. How else would you suggest I go about this? Is an email ban enough?

[rogerd]

Banning is complicated and often ineffective against smart abusers. In addition to IP and email address bans, consider some cookie-based approaches.

[Marcia]

>>3 flags and the post will be automatically removed

Whoooaaa... what happens if there are a few people around who just don't happen to like a certain person and they decide to gang up?

[ag_47]

Thanks for the replys. The cookie approach seems interesting, although again like you mentioned a smart abuser can get around no problem. I see. .. I guess I'll keep banning their emails.. I would like to refrain from touching IPs.

To Marcia: LOL, umm, good point. That's why I made it 3 flags, not 1 so people don't flag intentionally. I would hate to have to look at every single flag and decide whether something needs to be removed.
Keep in mind every user can flag a post once, so would increasing this number to 5 be reasonable. Or should I just consider doing it personally and later on appointing moderators..

[thecoalman]

Don't do it automatically but instead look at the flagged posts manually, I guess it depends on the amount of people you expect but you can also consider removing a posters ability to flag if they do it excessively without reason. That's a two way street....