Generally speaking, the justice system is our collective means to respond to crime. We bring criminals to justice. But there are voices, mostly friendly to the criminals, warning us that justice will further division at a time when we especially need unity. Justice, division, unity: these are complicated ideas with many possible meanings.
What is the proper function of justice? Revenge? Punishment? Compensation? A crime has been committed: what should we do about it?
A crime is a breaking of social bonds. The proper function of justice is to heal those bonds. Justice should be social therapy.
Punishment and compensation can work as components of a therapeutic program. No matter what, a path must be provided by which criminals can be reintegrated into society. Justice must exercise discrimination but never promote division. The wisdom of Solomon is indeed required to judge what form justice should best take in any given situation. We mortals are stuck bumbling along the best we can. But if we at least understand what we're trying to accomplish, that ought to improve results.
Unity: to the extent that it opposes diversity, it is a flawed goal. One image of unity is a watertight boundary surrounding perfect uniformity within. This is a kind of death. A vital society is a cohesive society. Cohesion means rich relationships among diverse components. Diversity without cohesion is merely plural unity, just as dead as singular unity. Society is a fabric, a network.
The core work of justice is in repairing and strengthening social relationships.