Some recent comment threads on Slate Star Codex, my favorite blog, have dealt with the always lively issue of gun control. One standard argument is "we know gun control laws work because the U.S., which has relatively few restrictions, has a much higher homicide rate than countries such as Canada or the U.K., which have much more restrictions."One response sometimes offered is that there are other countries, such as Mexico and Brazil, with both restrictive laws and homicide rates much higher than in the U.S. That then gets into the question of what comparisons are more relevant, in what respects the U.K. is more like the U.S. than Brazil is.An alternative approach, which I think more useful, is to ask whether the difference in homicide rates existed prior to the difference in regulation. The web makes that question much easier to answer than it would have been twenty years ago. In the case of the U.K., the answer is pretty clear. According to the Wiki page on Firearms Policy in the U.K., the first restrictive legislation was the pistol act of 1903, but it had little effect:
The Act was more or less ineffective, as anyone wishing to buy a pistol commercially merely had to purchase a licence on demand over the counter from a Post Office before doing so. In addition, it did not regulate private sales of such firearms.
The first significant restriction was the Firearms Act of 1920. There were additional acts in 1937, 1968, 1988, 1997 and 2006.The data on Homicide rates per 100,000: table { }td { padding-top: 1px; padding-right: 1px; padding-left: 1px; color: black; font-size: 12pt; font-weight: 400; font-style: normal; text-decoration: none; font-family: Calibri,sans-serif; vertical-align: bottom; border: medium none; white-space: nowrap; }.xl63 { vertical-align: middle; border: 1pt solid windowtext; white-space: normal; }.xl64 { vertical-align: middle; border-width: 1pt 1pt 1pt medium; border-style: solid solid solid none; border-color: windowtext windowtext windowtext currentcolor; white-space: normal; }.xl65 { vertical-align: middle; border-width: medium 1pt 1pt; border-style: none solid solid; border-color: currentcolor windowtext windowtext; white-space: normal; }.xl66 { vertical-align: middle; border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentcolor windowtext windowtext currentcolor; white-space: normal; }.xl67 { vertical-align: middle; border-width: medium 1pt 1pt medium; border-style: none solid solid none; border-color: currentcolor windowtext windowtext currentcolor; white-space: normal; }.xl68 { font-size: 10pt; font-family: Calibri; vertical-align: middle; border-width: 1pt 1pt 1pt medium; border-style: solid solid solid none; border-color: windowtext windowtext windowtext currentcolor; white-space: normal; } Year U.S. England&Wales Ratio 1900 1.2 0.96 1.3 1910 4.6 0.81 5.7 1920 6.8 0.83 8.2 1930 8.8 0.75 11.7 *1946 6.4 0.81 7.9 1950 4.6 0.79 5.8 1960 5.1 0.62 8.2 1970 7.9 0.69 11.4 1980 10.2 1.11 9.2 1990 9.4 1.09 8.6 2000 5.5 **1.71 3.2 2010 4.8 1.14 4.2 *No data for the U.K. 1940-1945**The figure is for the U.K. rather than England and WalesLooking at those data, it is hard to believe that the reason the U.K. has a lower homicide rate than the U.S. is restrictive legislation.My point here is not that gun control doesn't (or does) work. I wouldn't be surprised if some restrictions on firearm ownership reduced the homicide rate, but if so, the effect on the U.S./U.K. ratio is lost in the noise. My point is rather that the sort of factoids that show up in this sort of argument, even when they are true, are rarely as solid evidence as those who offer them claim. This would be a better post if I had a good example on the other side of the same debate. I don't, but perhaps someone reading this can offer one.