I'm all for looking at incarceration rates and sentencing disparities, etc. - if there are actual imbalances after controlling for relevant factors, then it makes sense to root them out and fix them.

That said, studies like the one you're citing appear to be flawed because they fail to account for rates of crime (especially violent crime) as well as socioeconomic factors. Correlation is not causation and all that.

(see e.g. https://www.wsj.com/articles/the-myth-of-systemic-police-rac...)