That's just a distraction. You KNOW that the family will receive a TON of wrongful death suits, and are probably in panic right now, trying to figure out how they are not responsible, and to blame everyone else for this tragedy.
They won’t be able to distract too much with the blame on guns since he killed three people with a knife, and one person with a car. That leaves two killed with a gun by my math.
Bingo!