Tribunal: Post Game Chat
One of the most pervasive problems I've noticed in LoL is the issue of opposing teams having to take your word for it when you tell them someone on your team is/was being toxic. The player can be extremely vitriolic in team chat but act like an innocent little angel in All chat. This gets even worse when the toxic player you're requesting a report for is in game with a duo partner or even a group of friends who vouch for him/her and manage to turn the entire enemy team against you too simply by virtue of having strength in numbers.
Why not allow both teams the ability to view the entire chat logs during the post game lobby? This way, all necessary evidence for opponents to make their choice on whether or not to report a player is available, and nobody can say "He didn't seem toxic to me (in all chat)."
TL;DR: allow both teams to view each others' chat logs to make reporting toxic players easier.