However, a lot of people are doing this, hiding behind alt when exposing someone's alt (when they are high ranked). Because they fear to get neg tagged or maybe they don't want to make enemies.
I've also exposed some high ranking users instead of newbie. Some of them have been proven guilty and legally tag. There's no reason to be afraid and hide behind alt if what you're trying to convey is true, even if proven guilty users are against the tag then I'm sure they won't have the power to stand against you.
It takes courage and enough reason to tag and accuse someone, if we are wrong then this will damage the reputation of other users. In the real world the police won't jail you for no reason and they won't make arbitrary accusations without being backed up by solid evidence, so they have to understand that the system works for the wrong things.