Telling tales: some episodes from the multiple lives of the polygraph machine
This chapter is about the polygraph device, more popularly known as the ‘lie detector’. The device has changed over time, though it has retained a central logic: specifically, physiological measures (e.g. blood pressure) are used as proxies for emotional responses created by the act of lying. However, this simple description might already go too far in prescribing a particular account of the device, since it will be the argument of this chapter that much of what the polygraph does can only be understood in relation to the contexts of its application. My argument focuses on the use of the polygraph in United States criminal trials and governance. Though it is largely assumed that the device is inadmissible in the US, the actual picture is more complex. Moreover, the adoption of the polygraph outside of criminal trials is similarly intricate, with the technology playing diverse roles in government departments, police investigations, dispute resolutions, post-probation programmes, surveillance, private investigation, family conflicts, media campaigns, in films and television, and a range of other contexts.