Our superego does not have to be necessarily accurate, fair, or compassionate. In fact, it usually isn't. Our first task as adults is to develop our own set of values. In other words, come to grips with all of the rules and injunctions we have received all our lives and sort them out. Then it is up to us to adopt our own rules.
Conscience is necessary.
It is imperative to know what is right and wrong. It is also imperative to know what to do when we have violated our own conscience. Yes, in fact we are our own judge, jury and executioner. The question is what kind of judge are we going to be, and what kind of jury is going to hear our pleas for mercy, compassion and understanding. A neurotic sense of guilt is characterized by its unreasonableness, its unfairness, cruelty and unrelenting demand for penance.