It goes way beyond that.
They were out of the “castle” and off the property.
The questions arise,
“Do citizens have a right to protect their property?”
“Do citizens have the right and obligation to stop crime?”
Citizens do not have the right to use lethal force to protect their property. This is settle law. (Katko vs. Briney.)
"He confronted Jack, and the rifle that Jack had just stolen went off during a struggle for it."
Read the article, the guy chased the perp, the perp had stolen a rifle. They stuggled over the rifle as the home owner tried to regain possession of his property and the gun went off. IMO, it probably went off because the perp was trying to shoot the victim and it didn't work out that way. The guy did NOT shoot the kid on purpose.
I wish every state had a castle doctrine law.
He was struggling to take his rifle back from the thief when it went off. That doesn’t sound like an intentional shooting. The burglary victim was not armed when he encountered the burglar.