So I've played against at least 4 scripters. They are literally scripting on the PBE now (urf). It's really obvious when someone scripts, because they usually have dodge scripts on.
Riot are also making an FPS game. They say their Anti cheat is #1 priority. Nice anti cheat, for league. It's like it doesn't exist. I've reported a bunch of scripters (through the support ticket) and to this day they're still playing. This means that their "evidence" for catching scripters is based on
1. Video evidence
2. Anti cheat catching them
The anti cheat seems to be easily bypassable.
What worries me is the fact they barely take action against them, unless they are super blatant. It's just stupid.