One report in a match holds just as much weight as 9. Its not the number of reports that matters its how often you get reported per game. That is also why asking others to report x player is considered harassment. It doesn't make a difference how many people report them so threatening to report and drawing attention is considered punishable.
Your reports are important though, but if you have spent a lot of time falsely reporting other players as a joke or out of spite then the weight of your report will go down. Also, you will only receive a notification that a player was banned if your report was final one that resulted in a punishment. Just because you see a player you think is trolling, feeding, or displaying bad behaviour in chat doesn't mean that is their consistent behaviour.
If you receive a suspension of any kind then you should also be provided chat logs from some past games. Should you not receive chat logs or should you believe there is an error please submit a ticket to Player support. Be aware that the chat logs will only contain what you typed and will not show what others players were typing. Riot deals with each player individually, therefore it in regards to you Riot will only take into account your actions and words. Other players that are legitimately deserving of a punishment will be dealt with accordingly.
