Fairness is an ethical value that is much in dispute and subject to interpretation. It's a tricky concept because each party most often maintains a different definition of fairness.
You might not be surprised that most prisoners don't consider their sentences fair. Since the laws are written to give judges a lot of leeway in sentencing, it's easy to find huge disparities in sentences for similar crimes. Many times judges are sentencing someone who they know very little about. Although there are processes in place to alleviate this problem, it does little to resolve the issue of proportionality.
Likewise, it can be said that many victims would argue that some sentences aren't harsh enough. It comes back to the matter of fairness. Because fairness is such a tricky concept there has to be a balanced approach. The standard of justice needs to include a process, impartiality and equity. Although these concepts themselves can be subject to interpretation.
Author Stephen Covey advocated for Thinking Win-Win (in "Seven Habits of Highly Effective People"). But I'm not sure there is ever a "Win-Win" for either the victim or the perpetrator of crime. There needs to be a fair standard of justice that holds criminals responsible for their crimes, while maintaining a balance of equity that gives room for repentence, restitution, and reconciliation. Obviously, not every circumstance allows for equity of this level, but many do. However, the State of Michigan rarely considers this necessary balance when pursuing a conviction and the resulting sentence.
Fairness in justice is a difficult concept to define, but it's less difficult to treat others with fairness in every day life. When you put others first you'll most likely always come out as fair. Are you fair in how you treat others? What might you change in order to develop the character pillar of fairness in your life?
