This is where you get into 'libel'. So someone goes on a site and posts something really bad about a business - something that can be seen as harmful and not substantiated with evidence. Its tough - really though the way these things have been settled in other places is that its the person making the post that is responsible, the website is just a vehicle. However, again its pretty grey.
Most of the time if people are really lawyering up and getting ready for war, it just makes sense to delete a few posts and calm down the situation. Especially when its one person just airing dirty laundry or something like that. Of course, sometimes a company is trying to cover something up, and we won't budge. Its important that the consumer has a voice and companies take it as customer feedback. If a product has a defect or issue, we want to be the vessel of communication for that consumer.
All of this shit is a massive grey area though. Really the second someone mentions lawyers, we shut down all communication with the person, cease all action to assist them and just get the two lawyers in touch. As soon as someone brings it out the conversation outside of lawyers is pretty much over.
Lawyers are no fun to deal with, but when someone goes there you don't have a choice.
