So, basically, the reporters went trolling on Lexis-Nexis and other databases to find "murder" within the same paragraph as "veteran"
or "soldier," and built a front-page story around that research. They compared the pre-war numbers to the post-war numbers and found that, voila!, there's a difference. And then it looks like they cherry-picked the best anecdotes out of that research (including the ones where they could get interviews and photos) to craft a narrative which fit the data.
The article makes no attempt to produce a statistically valid comparison of homicide rates among vets to rates among the general population. Nor does it rely at all on Pentagon data about post-deployment incidents of violence among veterans. It basically just generalizes from this small sample (121 out of 1.7 million Iraq and
Afghanistan vets, not including civilians and contractors) to conclude that today's generation of veterans are coming home full of rage and ready to kill.
I've got a one-word verdict on this article and its research: bullshit.