A polygraph test has the ability to measure and record different physical characteristics of the person who's being administered the test. The polygraph machine takes into consideration all of the physical attributes such as sweating, heart rate, blood pressure, and brain waves to significantly conclude if the person is lying or telling the truth. Interesting enough not all states apply the results of the test in the court ruling. For example, Georgia allows defendants who suffer damage because of a false result on a polygraph test (which are somewhat frequent) to sue the polygraph operator for damages and attorneys fees. .
Psychologist George Iacono, PhD, (1997) has argued, "the idea that we can detect a person's veracity by monitoring psychophysiological changes is more myth than reality." Even the term "lie detector," used to refer to polygraph testing, is a misnomer. So-called "lie detection" involves inferring deception through analysis of physiological responses to a structured, but unstandardized, series of questions." Therefore, a person administering the questions can provide bias results if the questions are asked in a certain format or out of context. Also, a person being prosecuted with a lie detector test will have an uncontrolled blood pressure and heart rate for the fear of being convicted on true or false accounts. .
The validity and accuracy of polygraph tests have been controversial since new psychological research findings in the early 1970's. George Iacono, PhD, (1997) states, "The underlying problem is theoretical: there is no evidence that any pattern of physiological reactions is unique to deception." Other psychologists argue that the placebo effect hasn't properly been tested when administering a lie detector test; therefore, some people may not believe in the efficacy of the procedure. Also, evidence indicates that strategies used to "beat" polygraph examinations, or so-called countermeasures, may be effective.
