A Switch of Dialect as Disguise

Criminals may purposely try to hide their identity by using a voice disguise such as imitating another dialect. This paper empirically investigates the power of dialect as an attribute that listeners use when identifying voices and how a switch of dialect affects voice identification. In order to delimit the magnitude of the perceptual significance of dialect and the possible impact of dialect imitation, a native bidialectal speaker was the target speaker in a set of four voice line-up experiments, two of which involved a dialect switch. Regardless of which dialect the bidialectal speaker spoke he was readily recognized. When the familiarization and target voices were of different dialects, it was found that the bidialectal speaker was significantly less well recognized. Dialect is thus a key feature for speaker identification that overrides many other features of the voice. Whether imitated dialect can be used for voice disguise to the same degree as native dialect switching demands further research.