[{quoted}](name=Riot Tantram,realm=NA,application-id=ZGEFLEUQ,discussion-id=MIBGEN1J,comment-id=0005,timestamp=2016-11-04T18:27:06.672+0000)
It has a list of phrases and words that are considered "negative". If a player is reported, the system compares the chat logs of the player to the list of words in the system. If at least 1 of the words the player said is in the list of negative words, the system issues a punishment to said player.
This is not how the system works. It is not a keyword based system. It also isn't that black and white. It is a machine learning system that learns from the community what is acceptable and what is unacceptable. It doesn't just say, 'they said a word on a list, they get punished.'
This is not entirely true. The amount of time it takes to be back in good standing is related to how severe your behavior was, what your last penalty was, how often you've been penalized, and you current behavior. Players who are having a bad day, penalized for behavior that is out of character for them and get a light penalty with be back in good standing rather quickly. Players with a history of poor behavior, those who frequently receieve penalties, and those exhibiting severe behavior will take longer.
The 3 month mark that is repeated on the boards is related to a quote saying it takes the average penalized player 3 months to get back in good standing.
The bold paragraph should help with your question.