The Role of Alcohol and Drug Consumption in Determining Physical Fights and Weapon Carrying by Teenagers

The purpose of this study is to examine the question of whether alcohol or drug use causes teenagers to engage in violent behaviors as measured by physical fighting, carrying a gun, or carrying other types of weapons. Simple OLS estimation of the effects of drug and alcohol consumption on violence may be biased because of the possibility that both behaviors are determined by unmeasured individual traits. Two-stage least squares estimates are employed to establish causality. This method first predicts consumption using the prices of beer, marijuana and cocaine and then enters predicted consumption in the violence equation. This technique allows the consumption measures to be purged of their correlation with unobserved characteristics. Data come from the National School-Based Youth Risk Behavior Surveys, which are nationally representative samples of high school students. Results indicate that beer and marijuana consumption do cause teens to engage in more physical fights, while cocaine use appears to have no relationship. None of the substances lead to increased probabilities of carrying a gun or other weapon.