No support. You would need evidence, and if there is a mod on, they will deal with it. /report doesnt show proof of the cause happening
As emerald said, you need proof. Just reporting someone doesn't prove they did anything. For all the moderators know, the person could just be lying to get someone in trouble.
I've seen a plugin for chat offenses that records and submits the chat logs up to 10 seconds before the command is typed. But it can only really be used for chat offenses. I think reporting on the forums is fine the way it is.