Yes they can get banned if the grief

Hello
If you'd like to apply for a mod rank, feel free to do so here: http://www.mineverse.com/applications/
Here is the template for it, I suggest you to read it all out first: http://www.mineverse.com/threads/updated-mod-application-template-read-before-posting.1/

I would also highly suggest you have the requirements done as well, if your app is up and you haven't met them,it will be ignored:
http://www.mineverse.com/threads/moderator-application-requirements.85774/

Thanks. I have been playing on the server for ages. Since it had Cops n Robbers. I hope to get to a point where I can apply for mod

Good luck