Should gun owners/purchasers become criminally liable for crimes and accidents that occur with their firearms?

There are no "accidents" when dealing with guns, the gun owner is either negligent or acting with a criminal intent.

In that case the father was negligent by not properly securing the gun and leaving it at the reach of a minor (there is no evidence that the kid broke into a properly locked gun locker.)

Prosecutors have filed charges in similar cases, unfortunately in this case the prosecutor decided not to do so, for whatever reason, and he can't be forced to do so even if we don't agree with him.

So, there are already laws against being a negligent gun owner, but it's up to the prosecutor to file the charges, or not.

On the meanwhile the victim's parents could still file a civil lawsuit.

A person is liable for the damage their automobile causes unless it has been stolen, what makes you think a firearm would be any different?

If the owner of a firearm has had his firearm stolen why should he be held liable for what the thief does with his firearm? That would kind of be like a person being held liable for a criminal who robbed a bank being held liable for the robber purchasing a firearm with money the robber stole from the bank and shooting someone with the firearm he purchased with the money he stole from the bank where you have your money in. What do you see so wrong with the one that commits the crime being held responsible for their own actions?

If they fail to take the necessary precautions and steps, then yes. For instance, if this guy failed to keep his gun in a secure location and left it within the reach of a minor and so forth, as appears to be the case here, then yes, some level of liability may be placed on him.

Obviously it has to be based on whether or not he took reasonable precautions and also what the nature of the accident/offense was. For instance, if someone's gun is stolen and he duly reports this to the police, and then six months later the same gun is used by the robbers to kill someone, he clearly shouldn't be held liable for that.

You might think so in some circumstances, but really, who would expect his 11 year old child would be capable of murder? If the kid had oppositional defiant disorder or some such, sure. But lacking evidence of something along those lines, it's downright bizarre.

The father is liable for improper storage of a fire arm and perhaps criminal negligence causing death.

gun owners are required to keep their weapons secure so they can be liable for criminal use of those weapons if they did not have the guns secured.

The boys father will most likely face charges.

NO. according to the liberal way of thinking only guns kill people. so if guns kill people then why are we jailing people for killing. if guns kill then the human should only be an accomplis to murder.