The polygraph, or lie detector test, is a controversial tool law enforcement uses to assess honesty. But how accurate are these tests and do they unfairly target certain groups of people?
We’ll take a closer look at the science behind polygraphs and their potential impact on those who take them.
They’re inaccurate and biased
Polygraph tests have been used for decades in a variety of settings. Despite popular belief, however, polygraph results are unreliable and untrustworthy at best. Studies have shown that the accuracy of these tests is highly dependent on the operator’s skill and can vary significantly from person to person. Further, they are highly sensitive to environmental factors and can be easily manipulated due to stress or exhaustion.
These tests may also be biased against certain groups of people resulting in false positives being found. This is because the tests are affected by physiological responses to questions and can be triggered by unconscious factors that may result in negative connotations associated with bias.
An unbalanced mindset or nervousness could easily result in a false indication of deception and result in the wrongful conviction of innocent people based on incorrect findings. Therefore, polygraphs are not reliable enough to be used as evidence in court and should be treated with caution until their accuracy is proven.
While polygraph results are not admissible in court, and the accuracy of the test has long been questioned, many people believe this form of interrogation is effective. Unfortunately, though, polygraphs can be used by police officers and interrogators to intimidate a suspect into confessing. The assumption that polygraph tests can determine between truth and lies is not accurately supported by scientific evidence and has resulted in many legal cases being found unreliable due to reliance on their results.