The July 13 "not guilty" verdict in the George Zimmerman Trial set off a firestorm on social media.  In the hours that followed that verdict, Twitter users took to the internet to express their opinions, both in support and in opposition of the outcome of the trial.  One such tweet that caught a lot of attention was this:

"In the 513 days between Trayvon dying, and today’s verdict, 11,106 African-Americans have been murdered by other African-Americans."

We turned to our partners at PolitiFact to see how the Truth-O-Meter did with this very number-specific claim.  PolitiFact writer Katie Sanders reports that the Twitter claim rates MOSTLY FALSE on the Truth-O-Meter. 

Sanders explains that the big problem with the number is that it is based on a 2007 U.S. Bureau of Justice Statistics report, and not on actual data between the dates of February 26, 2012 and July 13, 2013. 

The number that was cited in the tweet was a mathematical estimation based on the statistics that said, on average, 21.65 African-Americans were murdered by other African-Americans each day. 

The blog author then took that number and multiplied by 513 days to get his final result. 

Sanders said, "The impression that the blog post where the tweet originated from is making is that the black-on-black murder rate is much more significant than white-on-white, but that's not what the statistics say. Another problem with such a statement is that we're only talking about murders where the perpetrator and victim can be identified." 

Sanders also pointed out that the murder rate was lower in 2011 than it was in 2005, so the numbers, and the corresponding average daily rate, would be different.

PolitiFact contacted the blogger who authored the story to ask for clarification regarding the numbers and how they were applied.  The blogger responded by email:

"I think your criticism of the number I arrived at has some merit. I should have made it more clear that is the best extrapolation from the numbers that are available. While the FBI stats don't include all known cases, I don't see why the cases where race stats are known shouldn't be representative of the entire class of murders. Yes, it's true that murder rates have come down generally, which I'm pretty sure applies to all race/ethnic classes."

The claim does have some strands of truth throughout it. The statistics regarding the actual number of black-on-black murders for 2005 is accurate, but the interpretation and subsequent extrapolation of those numbers to then represent the period between Trayvon Martin's shooting death and the acquittal of George Zimmerman is problematic at best, which is why this claim rates MOSTLY FALSE on the Truth-O-Meter.