Joel,
It’s very hard to comment as I was not in the server at the time. If this occurs and you feel the need to explain yourself I would suggest that you send a PM to the admins that you were racing with in the server. They will offer you feedback and let you know of any improvements if needed based on what they saw.
As far as defending yourself, yes you are right you can. Remember however when a server gets messy like that just get racing as quickly as possible. Often you can get away and leave any slayer behind and the admins will do the rest. It sounds like there was plenty of admins in the server so I can imagine that the slayer went on to long anyway.