Tessling on My Brain: The Future of Lie Detection and Brain Privacy in the Criminal Justice System

Abstract:     
The criminal justice system requires a reliable means of detecting truth and lies. A battery of emerging neuroimaging technologies make it possible to gauge and monitor brain activity without the need to penetrate the cranium. Bypassing external physiological indicators of dishonesty relied upon by previous lie detection techniques, some neuroimaging experts believe in the possibility of reliable brain scan lie detection systems in the criminal justice system. Although philosophers, psychologists and sociologists have appreciated the complexity of distinguishing truth from lies, our courts are increasingly looking to neuroscience as a means of reducing the search for truth to the existence or non-existence of certain brain states. In this article, the authors assert that Canadian courts' current approach to protecting privacy cannot easily accommodate the challenges caused by these emerging technologies, examine the possibility of remote, surreptitious brain surveillance and address the potential threat to privacy this poses.

The article commences with an examination of the 'reasonable expectation of privacy' standard adopted by the Supreme Court of Canada, arguing that various courts across Canada have misunderstood and misapplied the Tessling decision by way of an inappropriate analogy. After a description of brain scan lie detection systems, the authors then examine the courts' use of the Tessling analogy in the context of brain privacy. In addition to demonstrating the danger in a generalized judicial proposition that there is no reasonable expectation of privacy in information emanating from a private place into a public space, the authors conclude that a more robust account of brain privacy is required and speculate about possible sources of law from which this might derive. The article suggests that the goal of using brain based lie detection in our criminal justice system will require better developed theories and understanding of privacy.

Number of Pages in PDF File: 17

Keywords: privacy, brain privacy, neuroethics, neuroimaging, cognitive liberty, criminal justice, Tessling, brain scan, lie detection, fMRI, EEG.

Accepted Paper Series