A friend and I have been talking on how to make forums safer as part of a class and while here is the system we came up with.
Warning: contains swearing, but is only used for examples to show how the system will work.
The program will actively search for words that are "deviant" in nature such as "fuck" and will show up. but one mention of this word will not give off an alarm, but lets say that "fuck" is used 20 times in a row on a single comment then the system will warn a mod or admin. The program will also find words that could be associated will each other. If the word "penis" appears in a thread nothing will happen but when "penis vagina and rape" appear then the alarm will sound. This could be used on threads, comments, and personal updates, but people are concerned about there PMs. If these undesired words are found in a single replay in a PM then the alarm will go off and message an admin/mod. It will not show the PM just the words contained. After more messages of the "undesired" nature are sent then the admin may message the owners of the PM and tell them that their content seems of a "crude" nature on the words that were flagged. The owners must then show mods/admins the content of the PMs and the mods/admins can either approve of the data or tell them to take their conversation to a different place. NOTE admin/mods will not look through and spy on your PMs, but if "sexually" words pop up then they will ONLY see them words.
I believe this program could be achieved by a plug-in and added to the server code. A premade one may already exist on the internet. And If I did not be clear enough quote me and I'll explain more.
Also do your part in keeping the forums safe. report people that are breaking rule. The punishment must be fair, understanding, and swift. Only report If it's really bad.