This authentic threat asserts impending fatal injury. Because of the dangerous nature of threats, investigators must immediately ask: Is the intent real? Is the threatener likely to act? With real lives at risk, using the linguistic information available to answer these questions quickly and accurately is of great importance. Yet, because most scholarship on threats has focused on behavioral characteristics, there is still a substantial lack of understanding of the discursive nature of threatening language and a lack of agreement, even, as to how threateners successfully threaten. For this research, I created a corpus of 470 threat letters, collected over one year at the Academy Group, a behavioral analysis firm of former F.B.I. Supervisory Special Agents. Approaching these threats through the construct of "stance," an author's culturally-organized feelings, value judgements, or assessments about a recipient or proposition (Biber et al., 1999), I utilize a triangulation of methods to uncover patterns of epistemic and affective meaning within the genre. First, through a survey of language ideologies, I synthesize how three communities of practice view stance in threats; our ideologies overwhelmingly construct a genre committed to violence and threatener control. Second, through a corpus-based analysis, I outline how grammatical markers of stance are actually distributed, uncovering an unexpected set of interpersonal functions--ones that ultimately "weaken" the threatener's stance. This finding is contradictory to the surveyed impressions about threatening language, which focus, rather, on functions that "strengthen" the threatener's stance. Finally, I present the discourse analytic findings from two threat cases; one of which supports and enhances the form-based functions previously identified, while the other challenges them, demonstrating how language, when viewed from a functional perspective rather than from one based strictly on patterns of form, can reveal more intimate ways in which interpersonal meaning is conveyed in this socially-deviant genre. This multifaceted approach offers a more comprehensive understanding of the theoretical construct of stance and the performative nature of threatening. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]