You should also include a TOS that explicitly prohibits the posting of falsefied data. Log IPs, require a valid email for signup etc. Use some weak encryption (ROT13) on the database, so that a valid login is required. (Make the DMCA work for you!) Heck, if you so wanted, you could explicitly prohibit access to any law enforcement officials. (Whilst this probably wouldn't actually stop them reading the site, it would give them a big disincentive to post false information - to do so would be tantamount to admitting cracking into your system.)

Hmm... maybe false entries by law enforcement officers could be construed as entrapment. Any lawyers in the house?