In our last post about eye blocking behaviour, we used video footage of Lisa Wilkinson responding to Karl Stefanovic's accusation of double standards, to illustrate increased blink rate as an indicator of stress. We mentioned how this is often seen in people when they lie. Another eye blocking behaviour that we mentioned, is when we close our eyes for a second or two longer than a blink. We often do this as a response, when faced with something we don't like.

These two nonverbal cues can be seen in video footage of Adeel Khan, who today, was found guilty of deliberately setting the convenience store alight and murdering the man who lived upstairs. Khan pleaded not guilty to all charges. In this video (at approx. 45 seconds), Khan's blink rate increases to 100 blinks per minute, in response to the question, "Mr Khan, I'll ask you, did you burn down the property?". There's a clear distinction between blink rate before and after the question. 

The second nonverbal cue we see here is eye blocking- when Khan repeatedly closes his eyes as he answers the question and further questions. Our brain doesn't like it when we lie, and so, we sometimes close our eyes, because we don't like to hear ourselves telling lies. On their own, neither of these nonverbal cues are indicative of deception, because, there is no single cue that is indicative of deception. Not even eye direction- which happens to be the biggest myth in deception detection- eye direction is NOT an indicator of deception. 

There's one more cue in the video, that added to the previous cues, could be taken as an indicator of deception- his avoidance in answering the initial question, "Mr Khan, I'll ask you, did you burn down the property?". Khan avoids answering the question by asking "What kind of question it is?".

So here we have a cluster of 3 cues that could indicate deception- clearly a red flag! I'm sure that if we were able to see his body, we would see a few more nonverbal cues to add to the cluster.