Across the population as a whole, neither homicide nor suicide is one of the 10 leading causes of death in the United States. However, for 15- to 24-year-olds, homicide is the second leading cause of death, and suicide is the third. The rankings are reversed for 25- to 34-year-olds. Considering these data by race, homicide is the leading cause of death for blacks ages 15 to 24 and 25 to 34. And it is the sixth leading cause of death for blacks at all ages.
To understand the relationship between gun violence and gun availability, it is important to have accurate information about gun ownership. How many firearms are there in the United States? How many households own firearms? How many handguns are there in the United States?
Because most states do not require registration or licensing of firearms and therefore have incomplete record-keeping, inaccessible data, and unobserved levels of illegal firearm ownership (Azrael et al., 2004), most firearm research must make use of alternative measures. The two principal methods for directly measuring the U.S. civilian stock of guns are (1) production-based estimates calculated from domestic manufacturing, export, and import data and (2) nationally representative surveys that ask respondents about gun ownership (Kleck, 1997).
Scholars have also used a varied list of indirect measures or proxies to measure firearms availability and ownership patterns, including the percentage of suicides or homicides committed with a firearm, the fatal firearm accident rate, gun magazine subscription rates, the National Rifle Association membership rate, the hunting license rate, and the number of federal firearm licenses (Miller et al., 2002; Azrael et al., 2004; Duggan, 2001; Corzine et al., 2000; Kleck, 1997). While all of these measures shed light on the relationship between gun ownership and violence, they also all suffer from measurement errors that are difficult to estimate.3 In Chapter 2, the committee recommends a program of research to improve the ability to measure gun ownership. For this section we use production and sales data to give the reader a rough idea of gun ownership in the United States.
Firearm production statistics are derived from reports of firearms manufacture, import, and export made to the Bureau of Alcohol, Tobacco, and Firearms. Estimates of firearm availability are derived by adding the net growth in the number of firearms (manufactures plus imports minus ex-
For a thorough discussion of the limitations of these measures, see Chapter 7.