Well this is off topic of off topic. Texas is #18 in murder rate. Most of the states with the highest murder rate are in the south and southwest. It's probably because of a variety of factors. IMO, the biggest factor is a culture of getting even and not backing down. Lax gun laws and very high levels of gun ownership are probably factors as well.
There are no northern states in the top 10 except for Missouri which is really in the middle.
I got the stats from here
http://www.deathpenaltyinfo.org/murder-rates-nationally-and-state. The website got the stats from the FBI website.
Russ, I am so sorry about your friend and his wife. That is too tragic for words.
Anyway, this is a reminder to be careful about robbery. It only has to happen once to screw up your life.