Question on Reports

So in my last game, I was an Annie. I got ganked mid around 11 times during laning, both by the opposing team jungler, and the botlane coming up. No one in bot pinged MIA. When I would run down the river to try to escape and hopefully have my botlane come help, they wouldn't listen to my pings. Then throughout the game my Lulu would call me trash (and in lobby tried to force a role on someone, then told them to suck his ****).

I ended to game around 1/11/4 or something with less than 100 CS. Granted I could've played more safely, but botlane could've also used pings besides the MIA ping when I died. It was obvious they were trolling and verbally abusing.

However, from what I think happened, my whole team reported me instead for feeding.

My question is, from what I think, the in game chat is taken into account when deciding for bans, and so are replays (this one I'm unsure about, verification please). If person A gets reported, can other people in that game become banned from their actions or words if they violate the game rules, even if they weren't the original target of the report?

Also, like I just said, what's taken into account when deciding bans/punishments? What does the staff look at to see if someone deserves to be banned?

Lastly, is the lobby chat taken into account when deciding bans? Like if someone decides to super troll pick and feeds, or decides to break the rules inside lobby?

I'm sorry if this is posted somewhere already, but I've yet to find it. Thanks!