Lie Detection Software Learns from Real Court Testimony

Machine learning is one of the hot computing topics of today. With Google releasing its own open source machine learning tools and both IBM and Intel not wanting to be left out of the party with their own offerings. Most of the uses for these platforms right now are almost entirely academic, with researchers frequently coming up with new and useful ways to employ machine learning in the real world. This has led to researchers at the University of Michigan experiment with utilizing it for lie detection.

In order to test out the system, as well as show it’s worth in a high-stakes environment, the researchers used footage of testimony from real court cases as their sample, claiming that the software was able to discern a liar with as much as 75% accuracy. Comparatively, humans could only reliably tell the difference between lies and truth 50% of the time.

The software made use of both the words and gestures of the speaker under analysis, using techniques ranging from simply counting certain words and gestures to where the speaker was looking in regard to the questioner and their vocal fill. The ability to employ these techniques potentially makes computers far better lie detectors than humans, according to professor of computer science and engineering Rada Mihalcea.

“This isn’t the kind of task we’re naturally good at. There are clues that humans give naturally when they are being deceptive, but we’re not paying close enough attention to pick them up. We’re not counting how many times a person says ‘I’ or looks up. We’re focusing on a higher level of communication.”

The team are not planning to stop with this, with plans to tie in the subject’s heart rate, respiratory rate and body temperature changes using thermal imaging. As well as this, they plan to let the system analyze and classify human gestures on its own, instead of through input by the researchers.

Gone could be the days of a suspect being hooked up to a polygraph lie detector that simply relies on the body’s physiological responses and draws the iconic graphs seen in many a movies. Criminals who think they can lie their way out of trouble could find themselves far harder pressed to deceive thanks to this.