I'm not particularly inclined to comment on the Trayvon Martin case -- it's been talked to death elsewhere -- but I have been noticing one particular piece of sophistry that keeps coming up over and over and over. It's a classic among the specious arguments that crawl out of the woodwork whenever racism is an issue: more blacks are killed by blacks than by whites.
So? And more whites are killed by whites than by blacks. Most homicides are committed by people who know the victim. You're a lot more likely to get shot by your brother-in-law or your next door neighbor than you are to get shot by a total stranger. If you're black, odds are most of your close acquaintances (friends and relatives) are also black so odds are anyone deciding to kill you will be black, too. If you're white, most of your close acquaintances are also going to be white so your murderer is likely to be white.
If, however, you have an incident such as the Trayvon Martin case -- someone shot by a total stranger -- it doesn't really matter that most murders involve acquaintances who share certain demographic characteristics. It's irrelevant. It's like looking at a case of arson and saying "But why aren't you talking about all the fires that get started by lightning strikes?" Tossing in black-on-black violence in an attempt to deflect attention from racism is specious, an attempt at sophistry to nullify concern about the real issues raised in the Martin case: possible racial profiling by a wannabe vigilante and incompetent law enforcement by the local police department. It's not as despicable as trying to retrospectively make a murder justifiable by smearing the reputation of the victim, but it still isn't pretty. At the very least, it's intellectually lazy. It also signals an unwillingness to engage with the reality of racism by trying to conflate two different issues and pretending that the existence of one problem means we can ignore the seriousness of the other.