It would be pretty easy to discriminate if you had loose underspecified rules, then decide action on a case by case basis. The problem seems to not be in the rules but in the deciding.
Why can't it be both? I once observed an instance very early in my career, while working in an employment litigation office where rules were explicitly created in order to box an individual in such that their actions, while completely legal and moral and in the course of their professional duties could be used as grounds for dismissal "because policy".
A lawsuit emerged. A settlement followed.
Just because "we made rules for this" doesn't mean the scrutiny should suddenly cease.
