How would a law have forced the gun to be locked up? The parents or anyone else who doesn’t care to do so, will still not do so. I keep mine locked up, behind my front and back doors or keep it with me. Of course, we have no one else in the house. When the grandkids come over, we lock them away though.
The problem is life happens, stupid people and even good people make mistakes. It seems like these parents were stupid, criminal and bad.
I am against holding parents as criminally liable for stunts their children pull, like stealing a car, or stealing a weapon and using them in commission of a crime. Leave it to a jury, not to legislative bodies. Jurists can make up their own minds when something goes beyond forgetful, to being criminally culpable.
Good posting that I fully agree with regarding all points.