Riot: shadow griefing needs a permante ban

Trolls are smarter than they use to be, they know not to talk in chat as that's an easy way to get banned, instead what they're doing now is shadow griefing. Such as stealing your lane, ruining your lanes xp(by standing next to you near an enemy), last hitting your minions, intentionally waiting to killshot. All the while padding their stats. This really needs to end because it's become an epidemic in ranked, these people know they'll never rank up, so they do their best to stop others from ranking up as well. And all the while laughing because they know they won't be banned.