I once had a dog who was very smart but if you yelled at her she would panic and not be able to correctly respond to instructions. She simply would not know what to do and would do the wrong thing hoping it was right. I have known people who responded the same way. This guy appeared to be one of them and it led to his death.
The moment he died for:
http://www.mirror.co.uk/news/world-news/cop-filmed-executing-man-hands-11659721
The woman's purse was in the way. He...did what? He was crying with fear (and with good reason), required to look directly at the ground and not ahead, encountered an obstacle, and...so he died.