It used to be legal for a civilian to own a civilian grade longarm - in most states that came out as: a rifle or shotgun with an action of single shot, bolt action, lever action, semi-automatic (one trigger pull one round fired), was not over .50 calibre if rifled, had a total length of 600 mm (2 feet) or more, a barrel of 450 mm (18 inches) or more, and had a butt stock (pistol grip only not allowed). All military grade weapon and full auto weapons were not lawful, except in very specialised cases. Hand guns required a special license and a real need - such as armed security guard or bank teller.
At that time the great majority of guns used by criminals were stolen civilian grade weapons sold on the black market. Most were cut down rifles and shotguns, a few were stolen pistols. Some were used in armed robberies, but most were used in gang wars. The laws were such that having an unlawful civilian weapon was only a fraction of the penalty for having a full military weapon; often it only resulted in a fine and confiscation unless it could be proven it was used in a more serious crime. Military grade weapons were more than ten times the cost of civilian grade weapons on the black market.
Following a major effort to disarm the civilian population after the Port Arthur shooting, the civilian grade weapons became unlawful to won except under a few very specialised situations, and even then the semi-automatics were unlawful no matter what. Rifles and shotguns were handed in to police stations, or confiscated, and destroyed. The civilian grade weapons became harder to get and the penalty for a military weapon and civilian grade weapon became the same. This has resulted in more of the military grade weapons being sold on the black market and more of them being owned and used by the criminals. Many of the older criminals have stayed with the civilian style guns they've had all along and are sued to, but the younger ones tend to go for the 'more bang for your buck' style full-auto weapons.
Luckily, the majority unlawful gun use has always been, and still is, for inter-gang warfare. The sad part is the rate of accidental shooting of bystanders has gone up a lot due to over spray of the bullets.
The police still turn up people who find rifles and the like amongst the effects of deceased older people who never handed them in. And the total number handed in is way short of the total number known to have been out amongst the public when the laws changed, but no one has any idea where they are.
One interesting factor that was recently told to me by an Army sergeant from a nearby recruit training camp is that the anecdotal evidence from the older instructors is that nearly none of the new recruits have any idea on how to safely or properly handle a gun or use one as they've not been near one before.
It would be fair to say that until the 1980s the majority of the Australian adult population knew how to safely handle and use a firearm, but now you would have to limit that to a very low percentage and then nearly all would be ex military or ex cops. In short, it's now a damn sight easier for someone to safely invade Australia without having to worry about the population taking up arms against them they have no idea how to do so. Yet, prior to the 1980s the civilian population could have put up a realistic defence by themselves.
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The most common weapon used by non gang associated criminals is a knife, even some of the younger or smaller gangs use knives only. Very few of the petty criminals (especially the career ones) go armed with any weapon at all as it makes a heck of a difference to the sentence if caught.
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personally, I believe in the right of the population to undertake proper training to obtain a licence to carry a civilian grade handgun or to keep a civilian grade longarm on their property. But the training would have to be a lot more than what you see the US citz getting. If the population had been armed as a matter of course I doubt any of the serious shooting we had would have gone so bad due to people being able to fight back. However, the real issue is not the guns but the people using them. The nutcases shooting people in a spree, and those standing behind the guns to stop the nutcases.
It all comes back to the citizens being prepared to stand up and defend themselves if they can, and far too many won't do that now because they've been too well indoctrinated by the government to be overgrown sheep. Thus arming them won't have any benefit, but arming the sheepdogs out there will.
Oh, almost forget. One down issue with the wholesale removal of rifles and shotguns from the civilian population in Australia - it's now almost impossible for the locals to keep the roos and rabbits under control as next to no-one goes out hunting them any more due to the lack of weapons and weapons skills.
