It's really hard sometimes when you have gangs of troll
s working together for support to realize what is really going down, that's why in all such questionable gamess, I start pausing and hitting the F12 key like crazy!
F12 Takes Screenshots in game, and places the images in a folder in the game directory, then I take those screenshots and upload them to image sharing and put links in the after game reports, and say something like: see chat logs, or if I am in a sassy mood, I say something thing like, "really riot? self explanatory... link to images"
That usually does the trick. Sometimes the best defense is a good offense and like Teemo says, always be prepared, because a lot of these kids are from broken homes and have no values or morality to speak of...