former Australian PM John Howard addresses the U.S. gun control debate

Nearing 20 years since the Port Arthur massacre in Tasmania in April 1996 in which a crazy with a semi-automatic rifle shot 35 dead, John Howard has told a U.S. audience: "It is incontestable that gun-related homicides have fallen quite significantly in Australia [as a result of tougher gun laws], incontestable."

He dismissed claims from critics that there is no evidence Australia's rate of gun deaths were affected by the change in gun laws.

"I mean, if you had 13 mass shootings [defined as five or more people dead] before Port Arthur and you had none since, isn't that evidence?

"And you had a 74 per cent fall in the gun-related suicide rates, isn't that evidence?

"Or are we expected to believe that that was all magically going to happen? Come on."

Australia's gun laws took the form of a national buyback of weapons, and heavily regulated access and storage of firearms. Australians do not have a constitutional right to bear arms.

Full article and videos

Of course, caution is always needed with statistics. There's nothing to say that because guns may not have been available, suicide attempters didn't choose another method.  Australia's homicide rate continued to drop year upon year after the measures taken in 1996, so gun availability wasn't the only factor.

The laws in NZ are more lax than in Australia.  Those in possession of a firearms licence can buy as many guns of the category they have a licence for as they like.  Those with a collector licence can buy anything they like including fully automatic guns, although these may not be fired. Pistol owners on the other hand are required to shoot 1,000 rounds a year at a range.

The standard method that NZ governments have of dealing with an uncomfortable subject is to appoint a commission of enquiry in the hope by the time it reports, the issue has gone away.  After the Port Arthur event such a commission was appointed -- and of the 13 main recommendations presented the next year none were adopted.

However, gun violence in NZ is quite low as is the homicide rate (1.0 per 100,000; Australia's is 1.1).