Rule 1:
Treat every firearm as loaded
Keep your finger off the trigger; always point the muzzle in a safe direction; open the action and inspect the chamber and magazine.
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Rule 2: Always point the muzzle in a safe direction.
Loaded or unloaded, always point the muzzle in a safe direction.
* A safe direction will depend on where you are.
Remember that bullets can go through walls and ceilings and they can ricochet against flat or hard surfaces.
* Never point a firearm at anyone or at yourself
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Rule 3: Load a firearm only when ready to fire
Only load a firearm when you intend to use it and only in an area where it can be safely and legally discharged. Remember to unload it when you have used it.
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* Do not load the chamber until you are ready to shoot.
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* Unload completely - no rounds in the magazine or chamber - before leaving a shooting area or entering a hut or camp. Double check.
Rule 8: Never have loaded firearms in the car ... or camp
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* Before entering a car, ...or camp completely unload your firearm.
* Ensure that the action is open and that there is no ammunition in either the breech or the magazine.
https://www.police.vic.gov.au/sites/default/files/2019-02/Safety Code Booklet.pdf
If RH had seen GL walking with his gun immediately prior to the verbal argument, why would he approach him? IMO he wouldn't.
To me it appears irrelevant whether GL approached RH or CC because he clearly broke the above rules, and but for that this sad tragedy would never have happened.
Unless and until I hear evidence that proves otherwise, in my books he's guilty as charged.
RIP Russell and Carol. There are so many people who will miss you both.