The Infraction system has been in place since 2002. I have not used it much, but, It is helpful when I can't keep track of who keeps "infracting(*TM)" and who doesn't.
Here is a screen shot of the infractions and the points assigned. Note that 90 points and you are banned for life. (Rough guide).
Assigning an infraction is more of an art than a science IMHO.... one I am just learning.
Hope that clarifies.
(*TM) Sorry - made up my own verb...