Fairness in reward and remonstration

A fundamenatal legal premise is:
"No person shall be punished but for an action violating a rule that was in force at the time when the action took place."

If my father was a murderer, no modern court of law would hold me responsible. Strangely, if my great great great grandfather had belonged to an oppressed section of society - identified by race or religion perhaps - I would likely be entitled to preferential treatment today, irrespective of my current living conditions.

There is a curious incongruity in the ways in which the modern world disseminates rewards and punishments. The law punishes individuals for what they consciously do. In contrast, government policies often reward groups of individuals for attributes they have no role in determining.