No matter who the legislature consists of, as long as there are no term limits, the NRA can purchase any legislator they want. All politicians care about is the next election. Nothing in between matters.

You are so right about legal gun owners and such. But regarding this person, chances are he bought the gun legally. Word is the suspect is a 69-year-old man so it's possible that Alzheimer's or other mental defect (for lack of a better term) may play a role  here.