I understand how you can't / don't have to track every mischief, however I feel that some offenses are in a grey area where some bad admin knows he won't have to produce proof and just lets himself slay/warn without much proof at all.
I feel it's worth pointing out that not only seasoned regular players but also (especially) newcomers can find themselves confronted with the impossible task of proving an abusive admin is wrong. The bad apples are few but they make a lasting iimpression on the public.
Again, my underlining these problems is only in the context of this ridiculous misuse of power.