Deltoid

Canada. Gun law in 78.

Homicide rate (per 100,000 population)
74-78 2.7 3.1 2.9 3.0 2.8 average 2.9
79-83 2.7 2.5 2.6 2.7 2.7 average 2.6

(a t test on the statistical significance of the difference of the means gives p=.01)

Thomas Grant Edwards said:

From "Gun Control and Rates of Firearm Violence in Canada and the United States" by R.J. Mundt, in Canadian Journal of Criminology, Jan. 1990, p. 137:

"The mean rate [of homicide] for Canada from 1974-1978 was 2.7, compared to a post-1978 rate (through 1988) of 2.6. One could admit the possibility that this decline resulted from the 1977 legislation, except that the mean rates for the United States in the same periods dropped from 9.2 to 8.9, and almost identical drop."

Wait a moment. I got 2.9 as the mean homicide rate Canada 74-78, not 2.7. Something is wrong here.

Let me have a look at Mundt's paper.....

Oh my goodness. Mundt has messed up badly.

Let me try to explain what has happened. There are two ways to count homicides. You can look at death certificates or police records. The numbers are a little different, but it doesn't matter as long as you don't mix them up.

I got the death certificate counts from the World Health Organization Statistical Yearbook. I got the police record counts from "The Size of the Crime Problem in Australia" (which got them from Statistics Canada 88). Mundt presents his data in the form of a graph. I extracted the numbers from this. In the graph, a 0.1 homicide rate corresponds to less than a millimetre, so these numbers are +/-0.1.

                    74  75  76  77  78  79  80  81  82  83  84  85  86  87
death certificates 2.5 2.7 2.4     2.5 2.5 2.1 2.3     2.4 2.3 2.1 2.1 2.2
             Mundt 2.5 2.8 2.4 2.6 2.5 2.5 2.1 2.4 2.7 2.7 2.7 2.8 2.2 2.5
    police reports 2.7 3.1 2.9 3.0 2.8 2.7 2.5 2.6 2.7 2.7 2.6 2.7 2.2 2.5

Can you see what has happened here? Mundt has used the lower death certificate numbers for 74-81 and the higher police report numbers for 82-87. This has the interesting effect of canceling out the decrease evident if either death certificate numbers or police report numbers are used.

How did Mundt go wrong? He states that the source of his data was Scarff 83 and Statistics Canada 88. From reading the paper you can discover that "Scarff 83" covered 74-81, so this is the source of his death certificate numbers, and of course "Statistics Canada 88" is the source of my police report numbers as well. Mundt's error is inexcusable, since the "Statistics Canada" reference contained data for 74-81 and he failed to compare these numbers with the "Scarff 83" numbers.

It is also interesting to compare firearm homicide rates and non-firearm homicide rates. After all, if both firearm homicides and non-firearm homicides decreased by the same percentage, it would be unreasonable to conclude that the gun law had any effect.

                                                                  ave   ave
          74  75  76  77  78  79  80  81  82  83  84  85  86  87 74-78 79-87
firearms 1.4 1.4 1.2 1.2 1.1 0.9 0.9 0.8 1.0 0.9 0.9 0.8 0.7 0.8  1.3   0.9
other    1.3 1.7 1.7 1.8 1.7 1.8 1.6 1.8 1.7 1.8 1.7 1.9 1.5 1.7  1.6   1.7
methods

t-tests show that difference in the means for firearms is significant (p=0.00003) while the slight increase for other methods is not (p=0.39).

Of course, here is the big kicker in Canada: Let's say you do believe that the pre-1977 murder rates are more than the post-1977 murder rates enough to make it worth your while.

"...there are now 1,275,000 more firearms in private ownership in Canada than when the Act was passed -- about 11,960,000, or 46,000 per 100,000 population."

Mundt has only counted gun purchases, he has not allowed for guns being sold/junked, so I don't see how he can draw this conclusion. In any case, number of guns per 100,000 population is an almost useless measure of gun availability. By this measure guns are equally available in the case where each of ten people has one gun and the case where one has ten and the other nine none. To put it another way, the gun purchases could have been mostly by people who already had guns.

"The stock of restricted weapons (almost all handguns) increased from an estimated 651,000 in 1976 to 923,000 in 1988 (based on the total number of restricted weapons registered with and reported by the RCMP."

There doesn't seem to have been any change in the handgun homicide rate.

So whether or not you believe murder went up, guns certainly did.

The relevant statistic would seem to me to be the percentage of the population with guns, and we have no idea whether that went up or down.

"When compared with the United States, trends in Canada over the past ten years in various types of violent crime, suicide, and accidental death show no dramatic results, and few suggestions of perceptible effects of the 1977 Canadian gun control legislation. This is scarcely surprising, except that expectations were high among the policy formulators, and some evaluations perhaps tried too hard to give them satisfaction. The decrease in use of firearms in robbery appears to be the only change that stands out over time or in comparison with parallel trends in the United States."

And I'm going to have to take exception to this as well. Lester (Psychological Reports 72(3 Pt 1) 787-790) has shown that firearm suicides were increasing before C-51 and decreasing afterward, while other suicide methods did not have significant trends.

When discussing accidental deaths Mundt says "Death rates from firearms accidents ... have been in long-term decline in both countries (Figure 6), with the American rate remaining from two to three times greater."

Looking at figure 6, we see that both rates decrease from 74 to 78, with the US rate being twice the Canadian rate both in 74 and 78. After 78 however, the US rate declines less rapidly, while the Canadian rate declines dramatically (by 75%!), with the result that in the last four years of the data set (83-86), the US rate is SIX TO SEVEN time greater. I'm puzzled as to what made Mundt think that it was only two to three times greater.

Conclusion: C-51 may have caused significant changes in the homicide rate, suicide rate, and accidental death by firearms rate in Canada.