The Way of the Gun: Estimating Firearms Trafficking across the US–Mexico Border

Abstract

The volume of firearms sold in USA and trafficked across the US–Mexico border is notoriously difficult to estimate. We consider a unique approach using GIS-generated county-level panel data (1993–1999 and 2010–2012) of Federal Firearms Licenses to sell small arms (FFLs) to estimate the realized demand for firearms based on the distance by road from the nearest point on the US–Mexico border. We use a time-series negative binomial model paired with a post-estimation population attributable fraction (PAF) estimator. We do so to control determinants of domestic demand. We are able to estimate a total demand for trafficking, both in terms of firearms and dollar sales for the firearms industry. We find that nearly 2.2% (between 0.9% and 3.7%) of US domestic arms sales are attributable to the US–Mexico traffic in the period 2010–2012, representing 212,887 firearms (between 89,816 and 359,205) purchased annually to be trafficked.