Too many times in the news, we hear stories of someone being shot unintentionally. When interviewed, the shooter says, invariably, "I don't know what happened. It just went off." This is, quite simply, almost never the case. Firearms in good working order do not just "go off." There are two kinds of "accidental" firearm discharges, negligent and truly accidental, and a simple set of rules to dramatically lessen the loss of life and limb from these discharges.
The Four Rules
There is a simple set of four rules of firearm safety which, if followed, eliminates virtually all death and injury from unintentional discharges. Here they are, in order (not of importance, in my mind, all are equally important), as they were taught to me and I teach them to people I take shooting.
Rule 1: All Guns are Always Loaded
I've heard this better stated possibly as "Know the condition of your weapon at all times" but it's simpler and easier to teach someone that, unless you've established for yourself to the contrary, any weapon you handle is assumed to be loaded, and you must conduct yourself accordingly.
Rule 2: Do not point a weapon at anything you are not willing to destroy.
Quite simply, unless you are ready and willing to damage, destroy, or remove something from this planet, DO NOT point a gun at it. You can't kill or injure someone with a gun if it's not pointed at them.
Rule 3: Keep your finger off of the trigger until you are ready to fire.
Guns that are in good working order and safe to fire require a mechanical action of the trigger to fire a round. It is that simple. Some triggers are very light, some are heavy, but if your finger isn't on it, the gun will not fire.
Rule 4: Be sure of your target, and what is beyond it.
Be aware not only of what your sights are on, but what is behind what your sights are on. Be sure your buddy isn't behind the trophy deer you're about to take, or that a truck isn't driving down the ridge you're using for a backstop. Also, make sure that you're not firing against a surface that might cause a dangerous ricochet, or any other hazardous condition.
Accidental vs. Negligent Discharge
As stated earlier, there are two types of unintentional gun discharges. A true accidental discharge is quite rare, and often related to either problematic ammunition, or a mechanical failing in the gun. These can be avoided by proper inspection and maintenance of your gun and ammunition.
The vast majority of instances where a gun "just went off" are actually cases of negligent discharge. These occur when an individual pulls the trigger on a loaded gun that he or she did not intend to fire. These tragic incidents are virtually eliminated by following the Four Rules above, every time a firearm is handled. Complacency kills, attention to detail prevents accidents.
Be safe out there.