Dunno. How many white guys with 72,45,39,17 prior arrests are released for similar crimes?
I blame the media for a lot of this. They've been teaching blacks to hate whites for decades and it resonates with some.
I think it is judges and media. I think many judges impose probation because they believe blacks are a disproportionately large portion of the prison population. The media and community organizers indoctrinate white hatred. The combination is deadly especially when mental illness is involved.