Understandably, research studies based on analyses of firearms trace data have been greeted with a healthy dose of skepticism. Although the quality of firearms trace data has improved over the past decade (Cook and Braga, 2001), trace data analyses are subject to a number of widely recognized problems (see Kleck, 1999; Blackman, 1999; Congressional Research Service, 1992).9 All are based on firearms recovered by police and other law enforcement agencies, which may not be representative of firearms possessed and used by criminals. Trace data are also influenced by which guns are submitted for tracing, a decision made by law enforcement agencies. Beyond that, not all firearms can be traced. The trace-based information that results is biased to an unknown degree by these factors.
Furthermore, trace data cannot show whether a firearm has been illegally diverted from legitimate firearms commerce. Trace studies typically contain information about the first retail sale of a firearm and about the circumstances associated with its recovery by law enforcement. These studies cannot show what happened in between: whether a firearm was legitimately purchased and subsequently stolen, sold improperly by a licensed dealer, or any other of a myriad of possibilities. As such, trace analysis alone cannot reveal the extent and nature of illegal firearms trafficking.
Ultimately, the validity of the conclusions drawn from these data depends on the application. In general, trace data are not informative about populations of interest, such as offenders, potential offenders, victims, and the general population.
Administered until recently by the National Institute of Justice, Arrestee Drug Abuse Monitoring (ADAM, formerly known as the Drug Use Forecasting program, or DUF) contains survey data and urine samples from samples of arrestees charged with felonies and misdemeanors at 35 sites across the county. Data collection occurred four times a year. Response rates were relatively high: about 85 percent of arrestees agreed to interview (http://www.adam-nij.net). ADAM focused on drug use patterns among criminal suspects and did not regularly collect data on firearms use. However, in 1996 researchers appended a “gun addendum” to the surveys in 11 sites to study patterns of gun acquisition and use among arrestees (Decker et al., 1997).
Decker and colleagues (1997) suggested how the addendum might be used to provide estimates of the frequency and characteristics of arrests in which the arrested persons owned and used firearms (National Research
Comprehensive tracing of all firearm recoveries reduces some of the problems in trace data introduced by police decision making. Jurisdictions that submit all confiscated guns for tracing can be confident that the resulting data base of trace requests represents the firearms recovered by police during a particular period of time.