The suspects were sent into the tent and told that pulling the "magic" donkey's tail would reveal the liar (if a guilty man pulls his tail, the donkey will bray).When the suspects came out, the priests examined their hands.Another, more informative method of detecting deception with some psychological validity, involved a donkey.
In ancient China dry rice was commonly utilized as a lie detector.
This means of deception detection was more advanced than a subjective evaluation of a suspect by a tribe chief.
As was assumed then – and is currently supported by more recent evidence – the nervous tension created by lying slowed or blocked the flow of saliva.
In Ancient Rome bodyguard screening was conducted using a similar method. It was believed that if a person blushed in response to provocative questions, he would not participate in plots.
Bodyguard candidates were asked provocative questions. African tribes have utilized their own method of detecting a guilty person.