That correlation is blatantly incorrect.
The cultural divide has existed for centuries. Many of the black people that live in America today are the descendants of slaves. Moreover, historically they've been relegated to second-class status: they tend to be poorer, less educated, have fewer opportunities, and therefore are more prone to criminal activity. Those that do manage to rise out of poverty face never-ending scrutiny.
All families usually give their kids "the sex talk" when they get old enough. But black families have the added burden of teaching their kids how NOT to catch the attention of a police officer.
Let's do the math. Approximately 700 officers over 6 years works out to be one death every three to four days. On the other hand, current statistics suggest that one black person dies at the hands of a cop EVERY DAY. See what's wrong here?
As for the White House not sending reps to civil funerals, there's a reason for that. Most law enforcement agencies are managed directly by the municipality, county, or state; the federal government is not legally obliged to go to the expense of sending a rep out every few days. If it were a military officer or someone who worked directly for the government, that would be a different story.
Perhaps one of the reasons that the President chose to send representatives to the funeral of Michael Brown Jr. was to show solidarity with the community, especially after all the unrest there. After all, the President is a black man. He probably understands very well.