I'd like to add a third possible reason for your consideration. Since "criminality" i.e. guilt of committing a crime is determined after a process engaging the law enforcement and justice systems, we have to examine whether there are inherent biases in those systems that result in skewed statistics. For instance, do police officers selectively target blacks for monitoring and investigation? Are blacks discriminated against in the courtroom as a result of procedure or human nature?
Do White Police Officers Unfairly Target Black Suspects?
https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2870189&...
Using a unique data set we link the race of police officers who kill suspects with the race of those who are killed across the United States. We have data on a total of 2,699 fatal police killings for the years 2013 to 2015. This is 1,333 more killings by police than is provided by the FBI data on justifiable police homicides. When either the violent crime rate or the demographics of a city are accounted for, we find that white police officers are not significantly more likely to kill a black suspect. For the estimates where we know the race of the officer who killed the suspect, the ratio of the rate that blacks are killed by black versus white officers is large — ranging from 3 to 5 times larger. However, because the media may under report the officer’s race when black offic-ers are involved, other results that account for the fact that a disproportionate number of the un-known race officers may be more reliable. They indicate no statistically significant difference be-tween killings of black suspects by black and white officers. Our panel data analysis that looks at killings at the police department level confirms this. These findings are inconsistent with taste-based racial discrimination against blacks by white police officers. Our estimates examining the killings of white and Hispanic suspects found no differences with respect to the races of police officers. If the police are engaged in discrimination, such discriminatory behavior should also be more difficult when body or other cameras are recording their actions. We find no evidence that body cameras affect either the number of police killings or the racial composition of those killings.
True, but there has been more than one paper written on the subject, which don't all agree with the one you linked vis over-representation for crimes.
The black/white marijuana arrest gap, in nine charts
https://www.washingtonpost.com/news/wonk/wp/2013/06/04/the-b...
As you're probably aware, black Americans are arrested for marijuana possession far more frequently than whites. You may also know that there's not much evidence that black people consume marijuana with greater regularity than whites do.
...And this is a uniform phenomenon. It's not that some states treat the races equally and others treat them really unequally. Only in Hawaii are the rates even close to equal, and that's biased by the fact that blacks make up only 1.6 percent of the population. In the state with the second-lowest disparity, Alaska, blacks are 1.6 times more likely to be arrested. In the state with the biggest, Iowa, blacks are 8.34 times more likely to be arrested. D.C. has the second biggest; in the District, blacks are 8.05 times more likely to be arrested.
There are lots of ways for the system to be racially skewed/biased without being a product of personal bias - so many that I think the focus on "racist police" makes it hard to recognize a lot of easily-provable problems.
Stop-and-frisk is my go-to example of a system that produces bias regardless of the race or biases of the officers involved. In theory, it's an efficient use of limited police resources, it can be implemented race-blind, and it "only catches criminals". There's room to talk about harassment of non-criminals, but at least regarding the people who get arrested its an understandable idea.
In practice, criminality is a product of conviction. Stop-and-frisk mostly catches 'possession' crimes like personal-use drugs and illegal weapons (and since a 3-inch pocketknife is illegal in many cities, we shouldn't mistake this for violent intent). As a result, living in a stop-and-frisk area massively increases your odds of being charged with a low-grade crime - it's not as though carrying marijuana or a Leatherman is rare among un-policed groups. Even if you attempt a crude race-blind implementation, like policing based on neighborhood crime rate, you end up with a vicious cycle where crime rates are high because enforcement is high.
So I think we do a disservice when we limit our discussion and investigation to officer bias. Even when it's not present, it's still easy to build an unequal system.
I'll defend the parent comment by observing that we can reproduce this effect with non-judicial metrics, like "murder rate in majority foo-race communities". Assuming the reporting rate for murders is very high across the board, this escapes bias in both policing and conviction rates, and sends us back to other explanations.
Even so, the policing/judicial question is really important.
There are some sociology results (I haven't seen a replication failure?) suggesting that not only race but stereotypical appearance within race influences sentence duration. There are all kinds of low-level-illegal practices whose effective criminality is shaped entirely by policing - think of any "side hustle", where selling loose cigarettes leads to lots of charges, but selling moonshine (the closest analogy I can think of) leads to relatively few.
More obviously, incidental discovery and stop-and-frisk policing produce wildly imbalanced charge rates. Walking down a city street with a pocketknife and pot is always illegal, but the odds of it being a crime depend heavily on who you are.
I'm not saying anything new, but it's a soapbox worth getting up on. It's a big deal in race, but it's also worth remembering the power of selective policing whenever we talk about criminalizing something widespread.
A community has a fair amount of power in deciding where crime happens. The police (by policy or culture) can choose to push illegal activity to certain neighborhoods. If the police come down hard on drugs, prostitution, etc. in white neighborhoods, then that activity will move to non-white neighborhoods. The problems that come along with increased illegal activity, including higher murder rates, will be concentrated in non-white neighborhoods.
