One of the great advantages of family constellation work is, that we look at what happened in the context of multiple generations. We try to look at the whole context that produced a certain behavior, or a certain event. If you look deep enough, you will ultimately understand any behavior, any act. Even if someone did something terrible, and caused a lot of suffering, you can look at it from a perspective beyond good and evil, where you are not interested to judge, but only to understand.
The superego work that students are required to do, is a fundamental exercise to become non-judgmental. You first have to stop your self-criticism; then you can stop being judgmental to others as well.