[mindslight]

Would the system be working well if only there were the correct ratios of demographic groups being oppressed by it?

Minorities have become the face of this issue because they are more likely to get caught up in the system in the first place. But the issue affects us all - perfectly non-racist cops would still run roughshod over plenty of people. What we need to repair is eventually-consistent justice so the murderers end up in jail (criminal) and wrongfully-harmed people are compensated for their losses directly from operating budgets (civil).

The injustice system has been allowed to degrade to its present state because most innocent people simply will not be harmed by it. It's only by getting the majority to see that injustice could have happened to them will you ever make them feel affected. Framing the issue around racism is ultimately self defeating - it turns the issue into one of those longstanding happens-to-other-people problems that people from the dominant group care about just enough to fit in/get laid/assuage conscience.