Even if the law worked mechanically, we still need to argue it in court, since the law cannot encode the complexity of the real world anyway. It is perfectly reasonable for someone to break laws, so long as they have sufficient justification for doing so.

For instance, you won't be guilty of violating a law if you are coerced to do so, and the court still needs to evaluate what level of coercion you underwent, and that fundamentally requires human empathy.

The law is not meant to be employed mechanically. It's there to make society more efficient when handling the easy cases.