Introduction (Polygraph) People have always wanted to distinguish truthfulness from lying in suspects of crime. In the past, there were many techniques to find out the truth from someone. However, the techniques were based on an assumption that some physiological effect would cause recognizable symptoms that could indicate truth or lie. An example dated early in 1700s. British novelist Daniel Defoe wrote an essay in which he said that taking a pulse of a suspect was effective to distinguish truth from lies.
In 1878, a researcher of Italian physiologist, Angelo Mosso, used an instrument called a plethysmograph in his research on emotion and fear in subjects during questioning. He noticed that blood circulation and breathing patterns changed under certain stimuli. In 1895, Cesare Lombroso, an Italian physician, psychiatrist and pioneer criminologist, modified an instrument called a hydrosphygmograph and used this device to measure physiological changes in a crime suspect in a police interrogation. Lombroso was the first person to use the instrument to determine truthfulness from deception.
In 1906, Sir James Mackenzie, M. D. , improved his clinical polygraph of 1892. Dr. Mackenzie’s improved polygraph resembled that of the modern polygraph. It was in 1921 when John A. Larson, a Canadian psychologist employed by the Berkeley Police Department in California, developed what many people considered the first polygraph. His polygraph was the first one that could continuously and simultaneously measured changes in pulse rate, blood pressure, and respiratory rate during an interrogation. Larson’s polygraph was extensively used in criminal interrogation.
Nowadays, polygraphs are widely used in many areas so people will need standards for polygraph. As a result, the American Polygraph Association and the American Society for Testing and Materials have established the standards for polygraph test. With the standards, people can rely on them. Mechanism Working Principle of Polygraph Polygraph works using a standard on the interaction between our mind and body, which will result an interaction to the environment, for example nervous, happy, and sweating, etc. In this polygraph testing we are expecting that the suspect will feel either nervous, shock, or no reaction, etc.
In consideration of the movement from the autonomic nervous system and sympathetic members of the autonomic system, the suspect will have mental and physical defense which will tell us how stress he is under the interrogation. There will be a graph that will show suspect nervous system that the examiner needs to pay attention to it, because from the graph the result will be interpreted. There are 3 systems from human body that will be analyzed. This is because if only 1 sensor, it will be quite hard to determine either the suspect is lying or telling the truth.
Hence, there are 3 sensors that the examiner can combine it and analyze the result. The sensors are: 1. Pneumograph (pneumatic tubes which is assisted by chains, fastened around the chest and abdomen of the person): It will measure the suspect respiration. If the suspect’s suddenly becomes unnatural, it will be shown very clear in the graph display. 2. Galvanometer ( 2 electrodes are affixed to 2 fingers on the same hand, and a current is running through it) : It measures how many moistures in your finger ( how much you sweat) 3. Cardiograph (a blood pressure cuff that is fastened in your arm).
It measures your cardio and blood pressure The examiner will analyze the result using data from these 3 sensors. If there are many unnatural fluctuations (sudden change), the examiner may conclude that the suspect is lying. When the fluctuation is normal (without sudden change) the examiner may conclude that the suspect is telling the truth There are 3 important kinds of question, which are relevant question, irrelevant question, and control question. There will be 9 – 10 questions are prepared, with 10 seconds break after an irrelevant question and 15-2 seconds following relevant or control question.
There will be repetition for each question at minimum 3 times. Control question is a standard or based to interpret the result. Control question is assumed as a base because the question will trigger mental or physical human body. For example, if the reaction for the relevant question is bigger than the control question, the examiner may conclude that the suspect is lying. Conversely, if the relevant question has smaller reaction that the control question, the examiner may conclude that the suspect telling truth. Therefore, we need repetition for each question to really know, whether they are telling lie or truth.
The irrelevant question is used only for disturbing the suspect concentration. The questions will be repeated but not in the same order. The real result from polygraph: Legend: 1st Line = respiration; 2nd Line = blood pressure #4 and #6 relevant question; #5 irrelevant question; #3 and #7 control question From the first picture (second line) the examiner can interpret that the reaction from the suspect about for relevant question (#4 and #6) has less reaction than control question (#3 and #7). Therefore the examiner can conclude that the suspect is telling the truth.
This conclusion is based on human nature that the truth telling suspect will not fell guilty or nervous with the relevant question because the suspect know and assure that s/he doesn’t do the criminal case. On the contrary, second picture (second line) showing that the relevant question has bigger reaction that the control question. Because, the examiner assume that the suspect will feel guilty, nervous, or even shock with the question. Therefore, the lying suspect is assumed to have this kind of graph. In reality, we know that human is extremely smart in deceiving the machine. Therefore the examiner needs more clues to conclude the suspect.
We will see more graphs. 1st Line = respiration 2nd Line = blood pressure 3rd Line = skin conductance 4th Line = cardiovascular change There are cases like this graph. For the first and second line, the reaction for question 3# and 7 # ( control question) are bigger than for question 4# and 6# ( relevant question). The examiner in this position will assume that this person is telling the truth. Then the examiner will analyze the next clues which are the third and fourth line. In these lines, it is shown that the relevant questions have bigger reaction than the control questions.
This graph is very common in the polygraph test; hence, the examiner will repeat the question, in order to get more valid result. There are still some other cases that the suspect trying to deceive the polygraph. For example, the suspect pretend to feel dizzy, amnesia, mental illness, or other mental block indicative of confusion. This is the graph that the suspect is trying to deceive the machine by pretending to have disease. The graph will have flat line. For the truth telling people, there will be no flat line like this. Because s/he neuron will continue to move never be constant.
There are still some cases that the examiner cannot conclude either the suspect is telling the truth or lie, because from the graph it is too suspicious and unclear. We know that if the suspect knows where the frailty of the machine is. Indeed the suspect can win from the polygraph. Hence, sometimes the examiner will give out “inconclusive” conclusion nowadays; ordinary people also can use this polygraph machine and already master and know how to interpret the result. Therefore, we should question how the accuracy of the polygraph actually works. Statistics
People’s attitudes towards polygraph Nowadays, polygraphs are being used more and more frequently in daily life. That provides a chance for more people to get to know the polygraphs and even to have an experience of using it. However, people hold different attitudes towards the polygraphs. Some people deeply believe in the result of polygraphs, while others think the polygraph is not as accurate as expected. We will explain the reasons of these two attitudes one by one. There are three explanations for why people agree with polygraphs. * Informational social influence
Informational social influence is the influence that leads people to conform as they see other people’s behavior as a source of information to guide their own behavior. Especially, people tend to show higher susceptibility to informational social influence when the situation is ambiguous. In this case, although the polygraphs are being widely used, most of them are used in professional fields. As a result, the perceptions of polygraphs, for most people, are ambiguous. Since people don’t know the polygraph is accurate or not, there’s conformity out of a genuine belief that what other people are doing or saying is right.
So they prefer to refer to what others’ believe in, which is, do agree with polygraphs. In this way, people regard the lie detectors are accurate due to informational social influence. * Obedience to authority Obedience is as basic an element in the structure of social life as one can point to. It is the psychological mechanism that links individual action to political purpose. It is the dispositional cement that binds men to systems of authority. In this case, most people know little about polygraphs. At the same time, there are scientists guarantee to the public for the accuracy of a polygraph.
They may further prove its accuracy by explaining the mechanism and demonstration. The communicators, the scientists, are authorities. People tend to regard them as credible. Meanwhile, the message consists of strong arguments. With reliable people’s persuasive words, people naturally obedience to authority and believe what they say, that is, to agree with polygraphs. * Desire for truth As Jill Carattini said, “In a world where truth is subjected to the murkiness of taste and opinion and the attraction to a self-evident, one-dimensional truth is understandable.
All the lofty humility of the abstract pluralist cannot beautify the noise of a million clashing voices and truth claims; eventually, we grow weary of the end product and seek a less polluted scene. In the words of the illustrious detective Joe Friday, ‘all we want are the facts. ’” That is true. Seeking for truth is the nature of human beings. Sometimes people are too eager to find out the truth and as a result, they overlook the accuracy of the method. That can explain why people still believe in the result of a polygraph, even though they do not know the specific mechanism of it.
Next, here lies two explanations for why people against the result of polygraphs. * Direct experiences of inaccuracy Learning is a continuous process in one’s life. Sometimes people learn through direct experiences. For example, some people may have the chance to use the polygraph and turned out the result was wrong. From this direct experience, he learned that the polygraph was inaccuracy. Therefore, he drew a conclusion of against the result of polygraphs. * Informational social influence Similar to the explanation of agree with polygraphs mentioned before, if you are surrounded by the voice of against the result of polygraphs.
You use others’ opinion as a guideline of yours. So you develop an attitude against the result of polygraphs later on. * Questioning the fundamental mechanism This explanation mainly focuses on people who have need for cognition. In other words, questioning the fundamental mechanism of polygraphs is likely to happen to who has a tendency to engage in and enjoy thinking about the polygraphs’ mechanism. As mentioned in the previous text, the mechanism of polygraphs is based on the physiology, such as blood pressure. And a standard line of lying is settled at the very beginning.
So if you think about it, you can actually cheat on the polygraphs by controlling your physiological signs consciously and setting a wrong standard line. Of course it is difficult to do so. However, with strict training, people can cheat indeed. And that becomes the scientific reason for against of the result of polygraphs. Examples of Polygraphs Example that lie detector works In May 1985, John Anthony Walker Jr. was arrested after his wife was given the polygraph test. Walker joined the Navy in 1955. He met Barbara Crowley while he stationed in Boston and married her after she was pregnant.
In 1967, John was assigned to the fleet headquarters giving him the access to see the communication between the headquarters and every U. S. submarine in Atlantic. During the time, John and his family’s financial status was in crisis. Walker decided to steal a classified document. He made a copy of a keylist, a code that can be deciphered into messages, and left the headquarters for the embassy of the Union of Soviet Socialist Republics to sell the document. There, Walker was confronted by a Russian, who was a KGB officer. Walker agreed with the KGB officer to provide more classified documents and in return for a monthly salary.
Once John accepted the offer, John was let out in a residential area with cash. John started spending a lot of money. Barbara was curious about his wealth. When Barbara confronted John, John admitted that he was a spy. Although Barbara was horrified, she accompanied John on his next dead drop site. John continued to steal keylists for the Soviet Union. However, in 1969, he was transferred to San Diego, California, causing him to lose access to keylists. Thus, John found one of his students, Jerry Alfred Whitworth, who John thought was an easy mark. Although John was transferred again to the Navy supply ship giving him he access to keylists, he was terrified that Barbara would turn him in if after she wanted a divorce. John decided that it was time to recruit Whitworth, so he would be able to tell his wife he was no longer a spy. It was time for John to retire and be a courier between Whitworth and the KGB. Walker also recruited members of his family, Arthur (his brother) and Michael (his son). Barbara promised to tell the FBI about their spying after she found out John’s wealth, while she was broke. John, on the other hand, didn’t take her word seriously. In 1984, Barbara told Special Agent Walter Price about John’s spying.
Price dismissed her story because she was drunk when they met. However, FBI Agents Joseph R. Wolfinger and Robert W. Hunter found that the dead drop sites Barbara described were accurate. As a result, Price gave Barbara a polygraph test and she passed. Because of the polygraph test result, FBI dug further. In 1985, John was arrested in a motel after his dead drop. While Michael and Whitworth confessed, Arthur tried to prove that he was innocent in the interview. However, the polygraph test showed Arthur was lying. Walker testified against Whitworth and helped the FBI to determine the damage he did.
Barbara was not prosecuted because she cooperated with the FBI to help with the spy ring. Example that lie detector doesn’t work In February 1994, FBI arrested a CIA employee, Aldrich Hazen Ames, and his wife, Maria del Rosario Casas Ames for committing espionage for Russia and the former Soviet Union. In 1985, Ames started spying for the Russians for money. He secretly named CIA and FBI human resources in the Soviet Union and also obstructed CIA’s secret operation putting many CIA officers at risk. In return, Ames was paid more than $2 million from the Soviet Union.
Although Ames was given two polygraph tests, which is a routine test for CIA agents every 5 years, during he was spying for Russia and Soviet Union, he actually passed both of the tests though he was lying. Ames took a polygraph test in May, 1986. He was tested on issues related to unauthorized contacts with a foreign intelligence service, unauthorized disclosure of classified information, and financial irresponsibility. Although Ames gave a deceptive response to whether he was “pitched” (to work for) by a foreign intelligence service, the polygraph didn’t detect any reactions to other issues.
Ames explained that the reason for his reaction to the “pitch” issue was that the Soviet Union was out there and he was worried about it. The CIA examiner asked a series of questions about the “pitch” issue to figure out the deceptive reaction Ames gave. Ames explained that he had been involved to pitch to get valuable information. Also, he responded that he might be known by the Soviet Union because of a defector and that he was concerned he would get “pitched” when he moved to Rome in 1986. Consequently, the polygraph concluded that Ames was truthful and non-deceptive.
Although FBI examined the polygraph’s chart in 1993, the deceptive responses were recognizable according to the FBI’s opinion. However, no additional detail was noted in Ames polygraph’s test. In 1991, Ames took another polygraph test. Before the test, CIA was suspicious about Ames’s unexplained wealth. Nonetheless, the polygrapher stated that the test would not focus on Ames’s financial status to make the polygraph test looked like a routine test. Once the polygrapher asked Ames a series of question, Ames eventually told the polygrapher some information about his financial status.
He said that the money he had came from his mother-in-law. The polygraph test asked Ames whether he was concealing financial difficulties. Ames answered no and showed no deceptive response. Ames also showed no deceptive response when he was asked that if he was working for a foreign intelligence service. However, when he was asked if he was concealing contacts with foreign nationals, deceptive reaction was shown. The polygrapher asked Ames to return and try to finish the test again since the polygrapher concluded that the test was incomplete.
Several days later, Ames returned for a second test with a different polygrapher. This time, Ames showed no deceptive reaction at all. The polygrapher concluded that Ames had passed the polygraph test. Because of the result of the polygraph in 1991, the investigate team became less suspicious of him. In 1993, the CIA and FBI began serious investigation on Ames. This investigation led to the arrest of Ames and his wife. From this espionage, the CIA was criticized for not taking action on Ames sooner. Alternatives Although we do not have polygraph to detect lies, there are some alternatives to catch liars.
We can detect lies by observing a person’s behavior. The behaviors we can observe are body language, emotional gestures, eye direction, and verbal behavior. Body Language * A person’s physical expression will be stiff when he/she lies. He/she will take up less space and try to move away from you. * He/she will avoid facing you. * His/her face can become flushed or whitened. * The liar tends to touch his/her face, throat, and mouth. He/she likes to scratch his/her nose or behind the ears. * Liar likes to put objects between you and him/her. The liar will be relieved when you change the subject. Emotional Gestures * Emotional gesture maybe delayed, stay longer, and don’t match with his/her words. * Emotional expressions are limited to mouth movement. When someone lies, he/she will only smile by his/her mouth not the whole face. Smile of a person who is lying. Natural Smile Eye Directions * A person who is lying likes to avoid eye contact and blinks a lot. * According to Richard Bandler and John Grinder’s book, “Frogs into Princes: Neuro Linguistic Programming (NLP) “, eye movements can help us recognize a person’s thinking.
People who are left-handed have the opposite meanings for eye directions. Visually Constructed Image (Up and to the left) * When people imagine a picture in their mind. Visually Remembered Image (Up and to the right) * When people create a picture in their mind from their memories. Auditory Constructed (To the left) * When people are asked to imagine and think about a sound Auditory Remembered (To the right) * When people are asked to imagine the sound they remember Feeling/Kinesthetic (Down and to the left) * When people recall about a smell, feeling, or taste
Internal Dialogue (Down and to the right) * When people talk to themselves From these eye directions, we can know what people are thinking and can catch people who lie. For example, your kid asks you for a candy and you ask him “what did his mother said? ” He looks at left and answers you “yes”. You will know that he’s probably lying. Verbal Behavior * The liar will take longer or shorter time answering your questions. He/she will sometimes imply answers instead of answering it directly. * He/she will repeat your words, or ask you to repeat what you said. Liar will elaborate the details. He/she will not be comfortable with silence and pauses in a conversation.
References 1. “How to Detect Lies and Spot a Liar Without a Lie Detector. ” Gecko&Fly. Retrieved from http://www. geckoandfly. com/2454/how-to-detect-lies-and-spot-a-liar-without-a-lie-detector/ 2. “How to Read People: Detecting Lies. ” Life Training-Online. Retrieved from http://www. lifetrainingonline. com/blog/how-to-detect-lies. htm 3. “How to Detect Lies. ” Blifaloo. Retrieved from http://www. blifaloo. com/info/lies. php 4. “Eye Direction and Lying. ” Blifaloo. Retrieved from http://www. blifaloo. com/info/lies_eyes. php 5. Earley, P. Family of Spies: The John Walker Jr. Spy Case. Trutv. Retrieved from http://www. trutv. com/library/crime/terrorists_spies/spies/walker/1. html 6. Bellis, M. “Police Technology and Forensic Science: History of the Lie Detector or Polygraph Machine. ” 7. About. com. Retrieved from http://inventors. about. com/od/fstartinventions/a/forensic_2. htm 8. “Brief History of the Polygraph. ” Home. total. net. Retrieved from http://home. total. net/~galcar/html/brief_history_of_the_polygraph. html 9.
Cite this Lie Detector – Polygraph
Lie Detector – Polygraph. (2016, Nov 28). Retrieved from https://graduateway.com/lie-detector-polygraph/