I'm real curious about the whole story on that one.
If the weapon was much more than a 22 pistol and the 4 year old doesn't have a bunch of broken or dislocated fingers or a busted wrist, I'd put the dad up for murder.
If the weapon was a semi-auto pistol and it was sitting somewhere cocked, loaded, and no safety, I'd put the dad up for manslaughter.
If a 4 year old managed to figure out and physically cock a semi-auto pistol, he should be put in a gifted program and should be playing some form of sports, because he's mighty smart and strong for a 4 year old.
If the pistol was a revolver, it's more likely to be a larger bore (hence the kid will have physical damage).
Either way, it's a two handed operation for a 4 year old to be able to hold the gun and pull the trigger. Tiny hands don't get leverage on a trigger if the fingers can reach it at all.
I'd also be curious to see how good a shot the 4 year old supposedly was.
Currently I'm leaning towards daddy telling the kid "you need to tell the police YOU did it so daddy doesn't go to jail and leave you all by yourself!".
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Don't Tread on Me
Overthrow the federal government NOW! ____________________________________