Has gun registration reduced the number of firearm-related fatalities? A simple analysis suggests that it has.
In the first figure I plot the number of firearm-related homicides and total homicides for the period 1979 through 2010. The total number of homicides peaked in 1991 and started a substantial decline after 1993.It leveled off in 2000 and now shows a smaller rise and fall into 2010. From the firearm-related homicides it is clear that the total number of homicides is following the contours of the firearm-related homicides.
But it could be argued that the U.S. is simply becoming less violent and that the fall in homicides reflects that. We can gather additional information by examining the number of suicides, total and firearm-related. If a more peaceful society is causing the decline we would not necessarily expect a decline in suicides. If background checks are the source, we might.
Total suicides rose until about 1986 and then remained level until about 2000 when a disturbing rise takes place. Firearm-related suicides started to decline in 1994 and continued until 2000. The decline is more pronounced than the total number of suicides but not nearly as pronounced as the decline in firearm-related homicides. The number of firearm-related suicides increases after 2005, but the increase is not nearly as substantial as the increase in total suicides.
We can also view the first two figures in terms of the share of homicides and suicides that involved a firearm.
Here we see that firearms form an increasingly large share of homicides until the Brady Act is passed, after which the share declines. The share increases after 2000, which might be related to internet sales. The share of suicides involving firearms was roughly level until 1994, when it showed a decline until 2007.
While there may be numerous confounding factors that weaken the result, this very simple analysis provides some evidence that background checks are reducing the number of firearms-related fatalities.