Freind Perma Banned for no reason

A close friend of mine was perma banned for using 3rd party programs.. He was reported by our teammate as it said in his E-mail. The only "cheating" program he had used were MK LOL (deleted it long time ago) and a custom skin installer (same,long time ago). Yes, he might have flamed or bannned some champ as a joke, but he hasn`t done anything with cheating. His Summoners name is **karlos1596**. If a Rioter is reading this, can you tell me why he was banned please
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