First link...an opinion piece, not worth reading.
Second link...uses terms like "suggesting bias" and "theorized" but offered no hard data.
Third link...it appears they combine a hodgepodge of data. For example, they put these bullet points together from an NAACP analysis, while blacks make up 13.4% of population they make up;
- 22 percent of fatal police shootings,
- 47 percent of wrongful conviction exonerations, and
- 35 percent of individuals executed by the death penalty.
But they don't dig into the percentages of how often someone refuses to cooperate with the police when stopped (broken down by race). If you resist, you're more likely to be shot.
They note blacks make up less that half of the wrongful conviction exonerations (which shoots down one of you earlier points).
They mention blacks make up 35% of executions, but the FBI has study after study showing blacks commit a disproportionate percentage of murders. Here is some free advice; Don't want to be executed? Don't commit murder!
All that said, is there bias in the system? Of course, because the system relies on humans and humans are biased.