Even if he weren’t lying, it would still be negligent homicide. If you point a gun at someone, you are responsible if they get injured or killed. Doesn’t matter if you pulled the trigger, mishandled the gun or a magic fairy pixie materialised and pulled the trigger for you.

The mere fact that you pointed a loaded gun at another person already makes you responsible per se in my book.

As much of a fan as I am of gun control, expecting gun owners to have a safe that is literally, physically impossible to break into is wildly unreasonable

Imo, if it was your gun, unless it was literally stolen from a locked gun safe, anyone who dies by it is automatically your fault.

Doesn’t really matter what the circumstances were. If anyone is even in a position to be injured or killed by your weapon, it usually means you acted negligently in either handling or storing the weapon.