The scenario is: despite evidence pointing back to the perpetrator who clearly murdered someone, he or she’s gotten away with it due to $$$ (bribing the judge on acquitting them despite DNA presence) which greatly infuriates those who insist on putting him or her behind bars, because of the fact they’re rich and manipulate the judicial system (corruption?).
In that case, only option without violence is to bestow karma (by definition: if one does something bad towards someone else, they’re retaliated with something worse in return), like for instance: they gotten away with murder because of bribery but lose something dear to them (family dies from an uncurable sickness) emotionally punishing the perpetrator.
Karma is a bitch as they say: so even if the perpetrator isn’t behind bars, there’s life revenge under the guise of unexpected events (like imposing bad omen on the perpetrator and their kin, kind of like a curse in a sense) tormenting their lives through sickness, disaster, 10 plagues by Moses, their kids get bullied at school due to their parent’s crime, etc.
The only thing victims can really do (without vigilantism) is wish spiritual vengeance towards the perpetrator which requires patience and belief in God. Even though the perpetrator may not be Christian or Catholic, most religions and faiths have a depiction of good vs evil: like their own depiction of heaven or hell, and condemn them spiritually when they die.
Like this: when the perpetrator dies - revoke their estate from being given to the beneficiary meaning they get nothing as punishment. Never give them a funeral or burial, instead an unmarked ditch without a tombstone where anyone can tread (unaware someone is buried) which their soul will be condemned to hell (devil) never ascending to heaven (god).
From there: God will know this person has murdered somebody in the living world getting away with zero consequences despite proof, is punished by being trapped in Hell forever with no chance of repentance. Their soul will just linger in a purgatory state without resting, like a restless ghost who may haunt people or locations where their body lays rest.