Male: 70%
Female: 30%
White: 49%
African-American/Black: 29%
Hispanic: 19%
Other: 3%
Thus 51% are non white police officers. So I guess if the entire police department feels that way, they probably have good reason, and it is not racism.
I suspect geography has as much to do with it as ethnicity. I would not try to raise a black child in Chicago, and police attitudes would be at the bottom of my list of reasons.