A look at statistics on black-on-black murders

The acquittal of George Zimmerman, a white Hispanic, in the shooting death of Trayvon Martin, a black teenager, has prompted commentary from the left and right about race and murder statistics.

We saw this statistic repeated multiple times by conservatives on Twitter after the July 13 verdict: "In the 513 days between Trayvon dying, and today’s verdict, 11,106 African-Americans have been murdered by other African-Americans."

We will leave it up to others to interpret the relevance of such statistics in the Zimmerman trial or other cases. Our role here as fact-checkers is to examine the numbers and their context.

A quick note on the case before we turn to the numbers: Hispanic is an ethnicity -- someone can be Hispanic and white, as in Zimmerman’s case -- or Hispanic and black. The crime data we reviewed generally focused on whites and blacks, though it sometimes included a generic "other" category.

Martin, 17, was unarmed when he got into a scuffle with Zimmerman in Sanford, Fla., on Feb. 26, 2012. A jury acquitted Zimmerman, a neighborhood watch volunteer whose lawyer argued self-defense, of second-degree murder and manslaughter. (Read our fact-checks that relate to the case and Florida’s "stand your ground" law.)

Statistic about blacks killed during course of Trayvon case

We found the claim about murders on the conservative soopermexican blog; it appears to have originated there. His blog walks readers through the math on getting to 11,106 deaths in 513 days. (We counted 503 days, not 513, but that’s a tiny quibble.)

The blogger, citing an earlier blog post and The Blaze, stated that there were 8,000 to 9,000 African-Americans killed each year -- 93 percent of them by African-Americans.

The numbers came from a 2007 U.S. Bureau of Justice Statistics report, which stated that blacks were victims of 7,999 homicides in 2005 and said that 93 percent were killed by people who shared their race. (It wasn’t clear to us where the blogger’s 9,000 figure came from.)

Using the number 8,500, that translated to 21.65 blacks murdered each day by other blacks. So the blogger came up with a mathematical formula: 21.65 times 513 days=11,106. That 8,500 figure seems high, though, especially if we look at more recent figures. The FBI reported for 2011 that 6,329 black people were murdered, for example.

The blog post makes it sound as if the black-on-black murder rate is particularly significant, but we found similar high percentages for whites.

The report also stated that 85 percent of white victims in single-victim and single-offender homicides were murdered by someone of their race. So that means the majority of black and white people are murdered by someone of their own race. In 2005, there were 8,017 white homicide victims. (Editor's note, May 21, 2015: We have since collected statistics on additional years and published those findings in a more recent report.)

The race victim/offender data isn’t shown for every case: It is only shown in the cases in which the race was known (some murders are never solved) and in cases involving a single victim and defendant.