Well if it wasn't in the champion ladder you out of luck as it seems the other ladders aren't moderated; however, these are the rules from the Champion Ladder:
In-game griefing includes using non-game mechanisms (such as continual use of the pause button) to harass your opponent. It will result in a ban. Again, please report such exploits to the admin team.
If you encounter what you judge to be bad behavior in the chat, you can contact Netheos directly on this forum by private message. Please send a description of the issue and any screenshots (F12) or files which might help to understand the case. It doesn't necessarily mean that we'll act against the coach you reported, but we'll look into the issue.
Hope this helps.