Kant wrote elaborately on the theory of justice. Sen then spoke intensely about the idea of justice. Both these sources are pivotal for anyone interested in moral philosophy. Yet, I believe, like a lot of Kant's and Sen's other texts, these too culminate into a paradox. They create a genius abstraction of a human need - justice, but in the process, discard a fundamental human attribute - emotion. Justice, to me, buds from an underlying sentiment to 'right the wrong'. It can be absolving oneself and enjoying the moment of innocence, or it can be seeing the perpetrator getting convicted for life to relieve those tears held back in the wait for justice. In both cases, justice is about the public validation of the coveted vengeance. You are well aware of your crime or lack thereof. In no way would you need justice if you were alone. The need for justice arises from the contingency of interaction with society. It's about proving something to others.
In another sense, justice is intimately connected with a prolonged and complicated presence of a feeling of vengeance. You want to have revenge against the one or the many who have wronged you. You want the others uninvolved and indifferent to know that you are the right one. You want yourself free of adversities. Consequences should be faced only by the perpetrators. Before getting justice, you don't care about what impact that might have on others. The focus is on the effect of the delivery of judgment on you. Any ripples for the future of broader society are a by-product. The sentiment of justice is vengeance. And yet, we are taught to bear tremendous shame about the feeling of revenge.
From ancient religious to modern legal texts, justice is synthetically and forcefully alienated from its underlying, if not causal, sentiment. In fact, the demand for justice is legalized, while the actions stemming from vengeance are criminalized. In such a system, the idea of justice is almost made an adversary of the feeling of revenge. This system then traps itself in a perverted manifestation of tendencies of vengefulness. There is probably no judicial system across the globe that's not heavily punitive. Only seldom and for "smaller" crimes of "better" humans, the legalized pathways of justice promote rehabilitation. In other words, we want criminals to be punished. We don't like people who commit crimes to get a chance to correct or change themselves. For instance, the intellectuals of India were deeply saddened when the police forces seemingly took the law into their hands to kill the rapists in a recent case in Hyderabad. They accused the police of exacting revenge under the garb of vigilante justice. However, the same people pushed heavily for capital punishment of juvenile rapists. They were okay when justice, as delivered by a group of aristocratic judges, killed a 14-years old who has admittedly committed a heinous crime.
The dichotomy is born out of the dissociation of the sentiment underlying justice and the theories and ideas of justice. Theories on and about humans and the systems built upon these theories that discard human emotions can only be expected to engender moral paradoxes and societal pathologies.