http://en.wikipedia.org/wiki/Race_and_crime_in_the_United_States
My points being that
1) murder is bad,
2) we ought to consider each murder individually,
3) people are innocent until proven guilty,
4) one hopes justice is meted out equally in all cases, and
5) if we really want to have a conversation, we should be looking at the ways in which we can reduce the prevalence of murder in the country.
The Trayvon situation stands out because it is such an anomaly. I tend not to focus on the outlier cases; Let’s look at the 16,000 murdered folks in the U.S. each year, and figure out what to do about that.