CSI: Crime Scene Investigation2000

Gil Grissom:
Truth is, a moral compass can only point you in the right direction; it can't make you go there. Our culture preaches that you shouldn't be ashamed of anything you do anymore and, unfortunately, this city is built on the principle that there's no such thing as guilt. 'Do whatever you want; we won't tell.' So without a conscience, there's nothing to stop you from killing someone and evidently, you don't even have to feel bad about it.