Abstract
This article describes a rising trend of chemical and biological weapons use among terrorist and rogue state groups. The author notes that, similar to the behavior of the perpetrator and victim in cases of interpersonal violence, predictive patterns begin to emerge when we study the behavior of terrorist groups or rogue leaders accused of using such weaponry. Due to the nature of chemical and biological arms, patterns of behavior occur over months or years prior to actual use. Citing the Lethal Violence Sequence as a unit of study, the article observes features of group baseline, pre-conflict, lethal event and recovery behavior that often accompany these attacks. Similar to other acts of genocidal killing, group history with regard to ethnonationalism, mass persecution, and hiding of atrocities become positive predictors of chemical weapons use.