Australia’s Gun Laws and Homicide: Correlation Isn’t Causation
In the wake of the March 15 New Zealand shootings, advocates for new gun restrictions in New Zealand have pointed to Australia as “proof” that if national governments adopt gun restrictions like those of Australia’s National Firearms Agreement, then homicides will go into steep decline.
“Exhibit A” is usually the fact that homicides have decreased in Australia since 1996, when the new legislation was adopted in Australia.
There are at least two problems with these claims. First, homicide rates have been in decline throughout western Europe and Canada and the United States since the early 1990s. The fact that the same trend was followed in Australia is hardly evidence of a revolutionary achievement. Second, homicides were already so unusual in Australia, even before the 1996 legislation, that few lessons can be learned from slight movements either up or down in homicide rates.
A Trend in Falling Rates
As noted by legal scholar Michael Tonry,
There is now general agreement, at least for developed English-speaking countries and western Europe, that homicide patterns have moved in parallel since the 1950s. The precise timing of the declines has varied, but the common pattern is apparent. Homicide rates increased substantially from various dates in the 1960s, peaked in the early 1990s or slightly later, and have since fallen substantially.
This was certainly the case in the United States. US homicides hit a 51-year low in 2014, falling to a level not seen since 1963. This followed the general trend: peaking in the early 1990s, and then going into steep decline. And yet, we can’t point to any new national gun-control measure which we can then claim caused the decline. In fact, the data suggests gun ownership increased significantly during this period.
Australia followed the same pattern, although national homicide data collection was spotty before the early 1990s:
Source: Standardized homicide rates per 100,000 population, four English-speaking countries, various years to 2012. See “Why Crime Rates Are Falling Throughout the Western World” by Michael Tonry.
Part of the reason that the collection of homicide data in Australia is so recent a phenomenon is because it has tended to be so rare. Politically, it simply wasn’t a national priority. Australia is a small country, with only a few more million peopl