OK. So. There's Jon Burge and the 'Midnight Crew', which tortured people into confessions (eletric shocks on genitals, etc) in Chicago in the '80s? Do you think those people they tortured were mostly white?

https://www.chicagotribune.com/news/criminal-justice/ct-jon-...

"Scores of African American men have accused Burge, who is white, and detectives working under him of torturing or abusing them during the 1970s and ’80s on the South Side. The scandal has stained the city’s reputation and cost taxpayers well in excess of $100 million in lawsuit settlements, judgments, other compensation to victims and legal fees ... In 2013, then-Mayor Rahm Emanuel issued an unexpected public apology for the damage done by Burge to the city, calling the era a “dark chapter” that needed to be put in the past. In 2015, a reparations settlement with some Burge victims mandated that Chicago Public Schools teach eighth graders and high school sophomores about Burge’s crimes. The curriculum went into effect in 2017."

The Chicago Tribune is not a liberal newspaper; it trends center to center-right.

https://en.wikipedia.org/wiki/Jon_Burge

"In 2009, the state legislature passed a bill authorizing creation of the Illinois Torture Inquiry Relief Commission (TIRC) to investigate cases of people "in which police torture might have resulted in wrongful convictions". In some cases, allegedly coerced confessions were the only evidence leading to convictions. Its scope is limited to people tortured by Burge or by other officers under his authority, as made explicit in the law and by an appellate court review in March 2016."

Or the murder of LaQuan McDonald in 2014 and the attempted cover-up?

https://en.wikipedia.org/wiki/Murder_of_Laquan_McDonald

"At the request of Illinois Attorney General Lisa Madigan, the United States Department of Justice initiated a civil rights investigation into McDonald's death and the activities of the Chicago Police Department. It released its report in January 2017, describing the police as having a culture of "excessive violence," especially against minority suspects, and of having poor training and supervision. DOJ and city officials signed a consent decree for a plan for improvement to be overseen by the courts. Moreover, three Chicago police officers were tried for allegedly attempting to cover up events related to the shooting and were found not guilty by the Cook County Circuit Court on January 17, 2019"

If nothing else the above shows us there is systemic racism in Chicago's police.

I leave the research for Los Angeles, New York, Atlanta, Memphis, Missouri, Alabama, etc, to someone else.

Here's a more general article, not specific to Chicago:

https://www.scientificamerican.com/article/a-civil-rights-ex...

"There’s powerful data collection that happens in our criminal courts. There have been studies showing that, all factors being equal, judges are rendering longer and harsher sentences for black defendants."

And the study linked to in the quote above:

https://www.jstor.org/stable/10.1086/320276?seq=1#metadata_i...

Here's another link to the same paper, w/an abstract:
https://www.journals.uchicago.edu/doi/abs/10.1086/320276?jou...

Racial, Ethnic, and Gender Disparities in Sentencing: Evidence from the U.S. Federal Courts

"This paper examines 77,236 federal offenders sentenced under the Sentencing Reform Act of 1984 and concludes the following. First, after controlling for extensive criminological, demographic, and socioeconomic variables, I found that blacks, males, and offenders with low levels of education and income receive substantially longer sentences. Second, disparities are primarily generated by departures from the guidelines, rather than differential sentencing within the guidelines ... Last, blacks and males are also less likely to get no prison term when that option is available; less likely to receive downward departures; and more likely to receive upward adjustments and, conditioned on having a downward departure, receive smaller reductions than whites and females. "

The author of the paper is an economist at the University of Georgia: https://en.wikipedia.org/wiki/David_Mustard_(economist)

Lastly - of course Black Lives Matter is politically motivated. That's the whole point! : )