I agree that you are making a point, and this point is responding to a position that isn't really being taken. We went to school together, remember, and we had friends that were black, white, brown, yellow (although I don't recall any Native American kids, now that I think about it). If someone is claiming that one ethnicity is free from civil liberty violations, then yes, they're probably trolling you.
The points that I see being made are: Local law enforcement has become more concerned with being in control than with the rights of American citizens (as has our federal government).
Police officers seem to use lethal force waaaay more on minorities. Which, possibly, have all been completely justified. Maybe minorities are just way more aggressive and dangerous overall and they all had it coming. It's possible, right? But until that's actually proven, why is it considered "controversial" to want an investigation into a police shooting? Might it have something to do with the person being black? If not, then what are some examples of other ethnicities being killed by police that have struggled to get an impartial investigation?
Finally, I think we all have stories of being harassed by the police. The trend you may notice is that, on average, minorities have waaaay more of these stories. I've been driving for 15 years. I've been stopped by police 31 times resulting in 2 tickets. 30 stops in AZ, 1 in CA. I got a ticket in CA, since I was speeding. My other ticket was for expired tags, in AZ, that had expired the day before and I got the ticket on my way to the DMV to pay my registration. That was just funny.
Is that a normal amount of times to be pulled over? Is it normal to have a stop/ticket ratio of 1-15? Might it have something to do with my skin color? I admit I don't know, really. It's only my personal experience.
But I don't think sharing my personal experience is further dividing the country. With our access to vast amounts of conflicting information, we have the luxury of deciding what we want to be true first, and then only accepting the information that supports what we already believe. It's not great for systems of democratic government, but on a philosophical level, I think we are finally going to see who people really are.