Do we have a foolproof way to know whether someone is lying or not? Human behaviour is complex and can deceive in a variety of ways. A polygraph test or lie detection test is a method that is widely used. But can the efficacy be challenged in some cases as most psychologists and scientists claim little validity of polygraph tests? For instance, an honest person may be nervous when answering truthfully and a dishonest person may be non-anxious.
Polygraph testing is an interrogation tool not a lie detector as there are many examples where people have trained themselves to beat this test. A case study of 2019 conducted in the United States flagged high false positive rates and noted that individuals can train themselves to beat a polygraph test. The psychological changes that a polygraph test looks for can be produced by states other than lying.
The ability to distinguish truth will always hold an allure. We believe in the lie detector test because we long for a form of justice that is swift, certain and non-coercive. After hundred years of mixed results, it is time to acknowledge that human conscience will neither be perfected nor mechanised.
Shafi Ahmed Khowaja &
Dr Pooja Merchant
Hyderabad
