The concept of disproportionality, justice, and police homicides

Ok, I haven’t been able to write much because I am both very busy and, frankly, heartbroken at the course of public events. Today we are discussing the Ferguson and New York decisions in my planning theory class, as it’s a good time to try to help people understand the idea of disproportionality. I worked up this fast little chart from Bureau of Justice Statistics data; the proportions are roughly the same for arrest-related homicide deaths from 2000 to 2010; the data year here is 2009 arrest-related deaths (homicide) and 2010 population percentages. I started fiddling with it after reading some really innumerate stuff that “white and black Americans have no difference in arrest-related homicide deaths” based on these data. I think that writer simply thought that, given the fact that the absolute number of whites killed is greater, there is no problem. No deaths are acceptable, but the fact that more whites die simply reflects their prevalence in the overall population.


In order to understand the problem, we need to look at the phenomenon proportionally. If we livd in a a color-blind world, we’d have a match, at least a rough one, between the proportion of those killed by the police as the general US population (as we do with Latinos and others). Instead, black Americans are disproportionately killed, and white Americans are disproportionately safe. This disproportionality is evidence of oppression. The numbers here for Hispanics and “Other” (Sorry, Asian friends to stick you all in “other”, but that’s how the BJS reports it) look roughly right. I don’t buy that there is no over-policing among Latinos, particularly in LA and other parts of the west and southwest, but it doesn’t show up in the police homicide numbers.

If you look at statistics for bad things: imprisonment, child death, disease mortality, dropping out of school, exposure to environmental stressors, etc, and if you find African Americans over-represented by proportion (and you will), it’s evidence of oppression.

When we talk about equality and justice, we are talking about roughly equal proportions across large populations. We’re not expecting one particular black person to have the same outcomes in life as one particular white person. We’re expecting statistical non significance in the race variable across large numbers…if we actually live in a post-racial world. (We obviously don’t.)

If oppression is not the causal factor, we’d need another believable explanation. And if you use rap music as an explanation, expect me to laugh at you.