By all accounts the biggest crime here was colossal stupidity. They were newlyweds (about three months, or so) and there has been no indication in any of the reports that either one had it out for the other. They were just not acting in a mature way in how they handled their firearms or practiced their drills.
The parents of the girl have said they don't believe that he meant to shoot her and that they believe it was and is a tragic accident.
It looks like he'll likely get convicted on negligent manslaughter and spend some time in prison, or maybe, if the court decides that having to live the rest of his life knowing what he did is sufficient punishment, just probation.
All in all, a very tragic event that was completely preventable.
This is helpful background info. While I agree that changing his story makes the individual look culpable, OTOH it should be possible to put together what other facts are known and come up with a most likely scenario. If the parents of the girl feel like it was an accident, that’s gotta be worth something. In many other cases of spousal murder(OJ for one, Brad Cooper for another) the parents feel very differently.
I've been following this story on the Omaha radio station KFAB since it happened. From some of the background stories about the couple it seems like they were both gun enthusiasts, but not very mature about it. Apparently they were part of a group that would post photos of themselves posing with their guns, pointing them at the camera (unknown if it was on a timer or an actual person holding it taking the picture), and they would blog about the various plans and methods they devised and practiced should they ever have to face an armed intruder in their home.