Ariel Linden & Paul R. Yarnold
Linden Consulting Group, LLC & Optimal Data Analysis, LLC
In 1997, Australia implemented a gun buyback program that reduced the stock of firearms by around one-fifth, and nearly halved the number of gun-owning households. Leigh and Neill evaluated if the reduction in firearms availability affected homicide and suicide rates, and reported that the buyback led to a drop in the firearm suicide rates of almost 80%, with no significant effect on non-firearm death rates. In this paper we re-evaluate the suicide rate data to assess whether any directionally-correct structural breaks in the time series could be identified prior to the buy-back program. Such a change in the time series prior to the intervention may confuse causal interpretation of the actual intervention.