In the case of a judge giving culprits "a break" based on sociological circumstances, I don't know that would even qualify as prejudiced either in all cases.
Obviously there's the strict definition which means "pre-judging based on characteristics", then there's the more contemporary Merriam definition of "The meaning of PREJUDICE is an irrational attitude of hostility directed against an individual, a group, a race, or their supposed characteristics."
...but even going by the strict definition.... If I'm a judge, and hear that someone's had a hard life, grew up in poverty, and grew up under negative systemic circumstances, and that information leads me to cutting them a break or being lenient, that's not pre-judging. Quite the opposite.
That falls into what I mentioned before, which is the concept of social bias.
Suggesting that any inequity (regardless of intent) = "racism" is just conceding to the far left's premise.
While I disagree with this judge's lenient decision, I still don't see where it comes from a place of thinking one race is inferior/superior to another.