The United Nations has not published any formal statement as to the legal framework governing peacekeepers' use of force when they are not engaged as combatants in an armed conflict. However, the United Nations has developed a working doctrine that it applies to all Chapter VII mandated missions, regardless of whether they are deployed into situations of armed conflict or not. This article analyzes this doctrine and its effects in practice, drawing on interviews with UN Legal Officers, relevant United Nations and human rights documents, and on information learned in the course of field research on the impact of UN operations to combat criminal violence in Haiti.