Empathy is at the core of justice. Without an ability to place oneself in another’s situation, it would be hard for us to criminalize many activities that we now do. Pyramid schemes, for example. The create the appearance of opportunity and the appearance of voluntary participation in the enterprise in pursuit of opportunity. But the opportunity is not, in fact, present. A justice without empathy would lead us to tolerate pyramid schemes (far more than we do). It is this exact sort of justice without empathy, without the ability of the men responsible for enforcing law and creating justice to imagine themselves in the situation of the victim, that is responsible for millennia of rape going unpunished and often unrecognized. Indeed it is only as women have taken a greater and greater role in enforcing law and creating justice that these rapes become cognizable by a system of justice, punishable by a system of laws.
Empathy is both necessary and good.
Understanding, however, is not necessary and it is too often not even good.