JZ's lies will soon be detected in court

[Caterpillar]

Psychopathy and fMRI Lie Detection
17 September 2012

Truth is an essential part of the legal system. Currently, anyone testifying is sworn to tell “the whole truth, and nothing but the truth”, as lies during testimony could have drastic effects on the outcome of a case. In the past, polygraphs have been used for lie detection, but they rely on physiological signs such as sweating and skin temperature to indicate when a lie is being told, and accuracy can range anywhere from 50 to 95 percent [1]. People are now turning to fMRIs for lie detection, as neurological function is theoretically more reliable than external signals in lie detection.

To detect lies with an fMRI, activity in the prefrontal cortex is monitored, as this area had been proved to become more active when a person is lying [2]. While studies have shown that fMRIs can detect lying with an accuracy of around 90 percent [2], results from these studies have been averaged over groups of people, instead of being based on individuals, and have focused on healthy controls.

People with pschopathy, a neurological disorder that results in fewer feelings of guilt or regret, make up 15-25% of the USA adult prison population and have significantly higher rates of violent crime than people without psychopathy [3]. Since people with psychopathy end up in court so often, it is important that lie detection work for them. However, psychopathy is associated with dysfunction in the amygdala and the prefrontal cortex, the area monitored for lie detection. Since the area being monitored is already dysfunctional, is it still possible to detect lies?

It would appear so. In a recent study, people with psychopathy experienced an increase in activity in the left and right ventrolateral prefrontal cortex when telling a lie [1]. This is consistent with data from healthy controls. However, the people in the study that produced these results were being told when to lie, which is quite different from trying to deceive someone. Future studies are needed to see exactly how much fMRI results differ from those of healthy controls and determine if the same standards can be used for people with and people without psychopathy. Regardless, the development of fMRI lie detection could very well change the state of our legal system. Testimonies could be fact checked prior to presentation to the jury. Psychopaths with a history of chronic lying could have their lies exposed. If the accuracy of lie detection with fMRI further increases, it could even mean a marked change in wrongful convictions.

http://neulaw.org/blog/1034-class-blog/ ... -detection . (DEAD LINK)