Investigating the phonetic and linguistic features used by speakers to communicate an intent to harm

This research aims to examine the phonetic and linguistic features which can be associated with a threatening intent. At present, there is a range of threat assessment resources and descriptions in legal cases which provide insight surrounding the content and production of threatening language. However, the veracity of these descriptions has not been thoroughly explored in empirical research. Through the examination of authentic and simulated threatening language data, this research provides a broad overview of the usage of phonetic and linguistic features to convey a threatening intent to harm. A set of 10 authentic speech recordings where a direct (or explicitly-worded) threat was present
were analysed in relation to a sample of non-threatening speech. In addition, simulated threatening and non-threatening speech and texts were collected from 41 participants under experimental conditions. These threatening and non-threatening data were compared with respect to mean fundamental frequency, intensity, articulation rate and changes to vocal tract features and vocal settings. The simulated data were also examined for the use of lexical features which have previously been associated with the actualisation of harm.

The results of these analyses suggest that there is no compelling evidence to support the assertion of a `threatening tone of voice'. There were, however, tendencies for these speakers to raise their mean fundamental frequency, intensity and articulation rate during threatening speech production relative to their non-threatening speech. There was also evidence to suggest that a number of lexical features used by these participants also corresponded to previous examinations of authentic threatening texts. It is suggested that on the basis of these findings, the production of threatening language is a considerably more complex and varied behaviour than might be expected. These findings have notable implications for the development of threat assessment tools, and for the description of a `threatening manner' in legal contexts.