Can someone being purposefully degrading and rude be banned?

I just played this ranked game against on of the worst players ever. He played Jax. After winning late against my losing bot lane he bm'ed for the rest of the game. Taunting people with their winrate and other garbage. He insulted many, not using any wrong words I think, but the way he used them were the worst. Told us to surrender, or that it wasn't worth the fight. I didn't get involved until late in the game where I told him to keep talking. Unfortunately I have trouble addressing since I am coming off of a ban and would not like a perm ban. This means I'm afraid to tell him that he is a scummy player that the community does not need. In the end the worse I said was that he was a "Jerk" and "scum" and if I get banned for that but he doesn't get banned I have lost faith in this community. Anyway, I really think that bming and other such rude behavior needs to be stopped. Riot says that "90% of players know its a competitive environment and that everyone needs to be treated with respect" but if this is the case then we have to stop the rudeness of the community. Anyway time to get off my soapbox. I hope there can be some discussion about this. For now I cri