This paper is based on data using similar methods collected from patients at 30 emergency rooms (ERs) in six countries. These data were analyzed with the goal of determining whether alcohol is a likely cause of violence through an application of criteria outlined by Bradford Hill. Analyses were conducted by comparing various measures of alcohol involvement in violent versus accidental injuries. The results supported temporal sequence of events and specificity. The odds ratios of violent versus accidental injury for a blood alcohol concentration (BAC) over 80 mg% were significant for each country, ranging from 2.77 for Mexico to 9.45 for Canada, which supports both the strength of associations and the consistency of findings. No third variables were found from the logistic regression analysis that better explain the relationships between alcohol and violence. A significant dose-response relationship between BAC level and violence was also found. All analyses conducted point to a causal role of alcohol in injuries related to violence.