The mode of violence of the countries studied have typically presumed that immigrants commit a disproportionate amount of the perpetration, whether "affective" or "predatory," is often debated by the prosecution and the defense at trial, and it may be central to the trier of fact's legal decision concerning criminal culpability and sentencing. "Affective" violence involves intense autonomic arousal, the subjective experience of emotion, reactive and immediate violence, internal or external perceived threat, a goal of threat reduction, possible displacement of target, time-limited behavioral sequence, instinctual behavior to reduce the treat, emotional/defensive action, and heightened and diffuse awareness. In contrast, "predatory" violence involves minimal or absent autonomic arousal, no conscious emotion, planned or purposeful violence, no imminent perceived threat, variable goals, no displacement of target, no-time limited sequence, a preceding private ritual to fuel narcissism and reduce paranoia, cognitive-based action, and heightened and focused awareness. This study measures the facts in a case study by the criteria of the two modes of violence. Following a week of separation from his spouse and temporary loss of custody of his son, the subject went to his wife's worksite and murdered her and the store manager, wounded a passerby in a car, and murdered a police officer who was arriving on the scene. Weapons used were a .32 caliber revolver, a 9-mm pistol, a 7.62-mm assault rifle, and a .50-caliber rifle. The fact pattern of the case is consistent with a "predatory" mode of aggression, that is, violence that is planned, purposeful, emotionless, and not preceded by autonomic arousal. 2 tables, 1 figure, and 11 references