Except when you are a public official it is your duty to pursue these sorts of cases for the public good.
If you're a peon, "doing your duty" is a great way to put a target on your back.
It seems like one of the hardest problems to solve in our society because it seems to be so tied to our nature. I can recall doing things in grade school I knew was wrong but felt obligated to do because my peers and those I looked up to do too. While that isn't the same exact situation, the dynamics at play are the same. What can be done to combat this innate in-group/out-group behavior more effectively in our organizations and society?