I think sometimes cases like this are used to bring in a commercial agenda---just like the gun insurance you mentioned, Simon. Instead of the guilty person (s) being punished, the whole of society will $pay$ for it in some way.
For no one to be held accountable for this is a miscarriage of justice and the judge should be sued through the Judges Association and removed from the bench and his portrait hung in a Hall of Shame.
The boys father should be sterilized so he doesn't have any more kids because he is too stupid and uncaring to deserve children. He should also be removed from the home and sent to parenting classes for a few years.
The man who demanded the father to sign the waiver---(a police chief, no less! who should have known better!) should have his hands cut off for presenting the paper and for loading and handing the gun over. He has no morals at all to use a tricky worded paper to absolve himself of responsibility. He should also spend some time in prison for his deed. Or better yet, let the next kid use him as a target since he seems to think this is innocent fun to promote shooting uzi's to 8 year old children.
And the jurors who allowed all to go scott free with no accountability should all be Baker Acted and have their heads examined.