Reports during pregame

I just queued up for ranked flex in a series with my buddy. I show that I want to pick Shaco and my friend chooses Darius. Support (1st pick Rengar) autolocks with ignite and I'm a little confused, but OK. Then our ADC Kai'sa gets her champion stolen and changed to something... Then our 3rd pick Mid lane with nothing said prior steals my Shaco pick and I'm like "Great, a premade of trolls. This is something I was really looking forward to."

So I'm like "Maybe he's not trolling, maybe he just didn't want to show his pick." So I say "Hey, Shaco, who do you want mid?"

He says, "I want ShAcO!!!".

I dodged and lost my series. But at least I avoided the match that would certainly have got me banned for verbal abuse.

I don't want reports that instantly punish, but if someone is absurdly toxic in champion select/receives constant reports for trolling/champion stealing, can there be SOME sort of punishment? Or at least someone reviewing players with 10 or more reports in their last 20 games? It's irritating that people can so easily get away with this, while I receive a loss in my series and 5 minute timer, this guy has no punishment and can continue messing around with others.