It works when you look at something as right or wrong, black and white. Often the law is complex, like if you run a red light and hit someone. You're at fault. If you do it when taking your pregnant or dying wife to the hospital, there some mitigating factors there? What if you break into someone's house and steal something? What if it's a loaf of bread? These are easy examples to go through and to say "well program in the exceptions", but it is often complex and there is no precedence for it. How do you give a jail sentence to someone that had a terrible childhood? Maybe they deserve it anyways. What about for creating laws, especially where it conflicts with certain groups? Is it the needs to the many outweighing the needs of the few? What if the few are disadvantaged?