What if every single one of those additional arrests is a Black person? Well that might require an additional look. It's possible that it's all Black people doing those crimes. It's also possible that the mathematician built an algorithm anchored on years of arrest data from racist cops doing racial profiling.
Will the mathematician be able to say, "hey cops can we take a second look?". No. Can the police be trusted to dig into the nuance themselves? Also no. Is racism active and documented in police departments across the country? Yes.
Should everyone who has any ability to do so stand up and say, we won't support this shit, which is what these mathematicians are doing? I think yes, but that's obviously my opinion.
That possibility is explicitly excluded since the data comes from crimes reported by victims, not investigations initiated by police officers.
Here's some real data: https://www.bjs.gov/content/pub/pdf/rpa11.pdf
Across all races and Hispanic origin, American Indians and Alaska Natives (15%) and persons of two or more races (15%) had the highest rates of reporting crime or neighborhood disturbances to the police. No statistical difference was observed between the percentage of white (9%) and black (7%) persons reporting a crime or neighborhood disturbance to police in 2011.
Also, perhaps I'm reading it wrong, but Appendix Table 4 suggests that minorities are much more satisfied with police response than the average.