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Background Information on polygraph aka lie detector tests

    The polygraph test, known popularly as “lie detector test” has been in use in the United States for more than a hundred years, since World War I.  In recent years, practitioners call it psychophysiological detection of deception or credibility assessment. They all refer to the same thing. Over the last few decades, the polygraph technique has proven to be one of the most powerful, robust and useful scientific tools in criminal investigations and personnel screening.  Among the most important applications of the polygraph test are counter-intelligence, counter-espionage screening, counter-terrorism and combating corruption. In recent years, polygraph tests are increasingly used for sex offender testing and monitoring.  Prosecutors routinely make use of polygraph tests to decide whether and which legal charges to file.

     It is well publicised that agencies like the CIA, FBI, National Security Agency, US Secret Service and the US Department of Defence etc employ polygraph tests for investigations and screening their own staff and contractors.  There is also widespread use of private polygraph tests on spouses, fiancees, girlfriends, boyfriends etc suspected of cheating brought about or exposed by social networking websites and smart mobile devices. Today, the polygraph test is used in more than 80 other countries world-wide, including China, Taiwan, India, Malaysia, Indonesia, Philippines, Korea, Japan, Israel, Australia, Canada, Dominican Republic, Mexico, Romania, Russia, Singapore, South Africa, Spain, Belgium, United Kingdom, Colombia, the Middle East etc.  The U.S. with between 3 and 4 thousand active polygraph examiners in the government and private polygraph companies is undoubtedly home to more examiners than any other countries. In the Asia-Pacific Region, Singapore probably rate the highest in terms of widespread usage by government as well as private sectors.

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Polygraph aka Lie Detector Tests Applications Overview

    In Singapore, the polygraph was first introduced by the Ministry of Home Affairs more than 45 years ago. In May 1977, Mr Koa Fung Chew, then an Inspector of Police and a senior specialist interrogator was sent to the American Institute of Polygraph Technology and Forensic Psychophysiology, USA for a 15-week training programme. Upon his return, the first Forensic Polygraph Laboratory was set up at the Ministry of Home Affairs. Since then, forensic polygraph testing has gained widespread usage - in practically all government law enforcement agencies - the Singapore Police Force, Corrupt Practices Investigation Bureau, Ministry of Manpower, Prisons Department, Singapore Customs, Central Narcotics Bureau etc, security and intelligence agencies and the military as a scientific tool for personnel screening, investigations and interrogation. The Prosecutor's Office also uses them to decide on charges to file.

      In November 2001, after his retirement as a Superintendent of Police, Mr Koa Fung Chew founded Polygraph Investigative Services, a government-licensed private polygraph company providing worldwide premier polygraph testing and training. Local as well as regional private companies and private individuals have engaged its polygraph testing services to help solve difficult workplace crimes and many other types of cases. We are a trusted Government contractor providing expert polygraph testing and consultancy services. (See list of Government clients).

      Polygraph Investigative Services undertakes extensive polygraph employee screening for local and foreign retail businesses as well as manufacturing industries where, despite tight security measures - theft, fraud, corruption, cybercrimes, money laundering, counterfeiting etc commited by employees in collusion with vendors and syndicates, pose a serious challenge. Foreign government agencies have also engaged Polygraph Investigative Services to assist in their criminal investigation, training and setting up of polygraph testing facilities. Polygraph Investigative Services conducts polygraph tests for clients from Asia-Pacific Region, including Australia, Malaysia, Indonesia, China, India, Hong Kong, Taiwan, Thailand, South Korea, Brunei, the Middle East - Bahrain, United Arab Emirates, Qatar, Saudi Arabia etc. These polygraph tests were carried out locally in Singapore as well as in countries where our clients are located.

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How Does A Lie Detector Test Work?

    A polygraph (popularly referred to as a lie detector) is an instrument that measures and records several physiological indices such as blood pressure, pulse, respiration, and skin conductivity while the subject is asked and answers a series of questions. When conducted by a competent and experienced polygraph examiner, deceptive answers will produce physiological responses that can be differentiated from those associated with non-deceptive answers.

    At the outset, the examiner obtains a complete background information on the case. The polygraph test or examination proper consists of 3 phases.  During the first phase, the pre-test phase, the examiner discusses with the subject the test issue , thoroughly reviews all of the test questions that will be asked during the test,and assesses the subject's emotional and physiological suitability to undergo the polygraph test.

    The testing phase consists of a series of tests where the subject's physiological responses are recorded as the subject answers a set of questions reviewed earlier.  The polygraph theory, is based on psychophysiological principle, is that when the subject hears a question which he or she intends to lie, the brain interpretes and triggers automatic and uncontrollable phsiological changes captured by the polygraph.

    During the post-test phase, the examiner reviews all test data obtained and interprets the polygraph charts, from which the examiner will reach one of 3 conclusions – that the subject is telling the truth; that the subject is not telling the truth; or that the results are inconclusive.  Upon completion of the test a verbal report will be given to the client, followed by a written report which consists of a synopsis of the case information, a list of the relevant test questions, the subject's answers, and the examiner's opinion as to the subject's truthfulness or deception.

     Polygraph tests are strictly voluntary in nature and do not violate a subject's human rights. Each polygraph test normally lasts between 1.5 to 2.5 hours.

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Are Lie Detector Test Accurate?

    There are now about 25 research studies available on the accuracy of the lie detector tests.  In ‘real life’ cases, researchers have found it very difficult to assess the accuracy of polygraph examination because the ‘ground truth’ criteria are often lacking i.e. it is not possible to find a representative sample with which one can establish with certainty who is and is not actually telling the truth.  Based on the studies now available, experts assess the accuracy of polygraph examinations administered by a highly competent examiner to be higher than 92%.  Like in many other scientific diagnostic procedures, the level of skills and experience of the examiner plays an important part in the accuracy of the examination. Comparative studies have shown that polygraph tests yield an accuracy that equals or exceeds that of many other forms of evidence.  In one study, it was shown that polygraph tests produced an accuracy that was comparable to results obtained by document examiners and fingerprint analysts, and exceeded that of eyewitnesses.

    In many ways, seeking a good polygraph examiner is similar to seeking a good surgeon. It pays to get a surgeon with a good track record although you may pay more. Similarly, an examiner with a good track record and reputation increases your probability of success in arriving at the truth and avoid disastrous mistakes.

Are Lie Detector Test Used In Court?

    Although the polygraph test has been in use in the United States for more than a hundred years since World War I, this technique is relatively new in the Asia Pacific region.  There is no precedence or court ruling on the admissibility of polygraph evidence in most of these countries, including Singapore.  In Japan, India and Indonesia, polygraph evidence is admissible in court.  In the United States, most states permit polygraph test results to be used as evidence where parties have agreed to their admissibility before the examination is given, under the terms of a stipulation.  In one US state, New Mexico, polygraph evidence is admitted in the same way as other scientific evidence.

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How Does The Polygraph Test Serve As An Investigative Tool?

    'Smart’ offenders commit crimes in such a manner as to cover their tracks and make it difficult to identify the culprit or to prove guilt.  Sophisticated crooks, especially the master minds, know how the authorities operate and they resort to countermeasures.  In the workplace, the culprit could be one of many staff working in an office but there are no leads.  Such a scenario is typical of many crimes committed.  Routine police investigations in such cases may end in a ‘dead end’ and the employer winds up having to live with the uncaught offender.  Investigators find themselves in situations where there is a complete lack of information/evidence, information gaps or only circumstantial evidence.  Often, it is a case of one man’s words against another.  At other times, different people give grossly different versions of the same event or a person gives an account that cannot be independently verified.  In such situations, the polygraph test is the most effective means to determine the credibility of a person’s statement.  It expeditiously and accurately guides the investigators to channel resources in the right direction by exonerating the innocent and narrowing down suspects or identifying the perpetrator. 

    In law enforcement scenarios, the interviewer is often faced with a situation where a suspect keeps changing his account and leading the interviewer up the garden path. The polygraph is the most effective tool against such an interviewee. Investigative resources can then be focussed on gathering evidence on the culprit.  Many a times, this leads to the guilty confessing his crime through a combination of skilful interviewing and polygraph testing.

    On the other hand, the polygraph test can also be used for less complex cases like determining the credibility of the statement of a witness, informer,suspect or an accused person in any investigation, or just an individual involved in any dispute, including marital or fidelity issues. Over the years, Polygraph Investigative Services has successfully helped clients to solve cases involving employee theft, commercial fraud, corruption, violent crimes, drug offences, industrial espionage, and threats to corporate security.

    One of the most difficult type of cases to solve is the "inside job" e.g. espionage, collusion between employees and outside criminal syndicates, between employees in different internal departments and between senior and junior staff, terrorist acts committed with insider help etc. Here Are Some Interesting Cases Handled by Polygraph Investigative Services which would have otherwise gone unsolved...

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How Does The Polygraph Pre-Employment Screening (Background Check) Help Secure My Business?

   While most job applicants are honest and hardworking individuals, some of them try to gain a job by misrepresenting their background, employment history, education, experience, and abilities on their resume and application. A recent research done by the National University of Singapore Business School showed that 82.3% of respondents misrepresented or exaggerated their abilities in their resumes. Consequently, some individuals are hired who eventually put the employer, co-workers, and members of the public at risk because of their inappropriate behaviour.  Many employers do not even institute pre-employment background checks on their employees because they do not realise its importance before it is too late. For instance, recent news reports surfaced cases of under-aged domestic maids falsifying their age by using forged documents provided by sponsors to obtain employment in Singapore and other countries. In other cases, sexual perverts are employed as teachers in schools and institute of higher learning. Some employers rely on perfunctory screening methods like interviewing, checking with characters referees and past employers which are inadequate, especially for positions of trust.  Furthermore, conventional methods for background checks cannot be used to screen foreign employees, or job applications with no criminal records.

    Even for organisations with access to criminal and other official records, they find that such records are inadequate. For every crime solved, there are many others which remain unsolved or undetected.   It is for this reason that many well-known organisations like CIA, FBI, US Department of Defence and private sector organisations rely on polygraph pre-employment screening.  Polygraph screening often reveals reliable information not obtainable by any other means.  These include concealing/falsifying background information or qualifications, criminal records, undetected crimes like theft from previous employers, fraud, corruption, drug offences, sexual crimes, violent behaviour, membership of undesirable or subversive groups and other unsuitable behaviour. According to a Washington Post news report, the polygraph is a vital component of FBI's security program. The FBI now conducts about 8,000 polygraph tests each year, most of which involve current employees, applicants and contractors. All applicants and new employees undergo a polygraph at the FBI, and nearly every employee -- including the director -- is subject to a new test every five years.

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How Does The Polygraph Periodic Screening Help Secure My Business?

   Periodic polygraph employee screening is akin to an organisational ‘health check’ to detect workplace crimes and malpractices early, before the cumulative effect results in considerable financial loss, damage to reputation or even bankruptcy. A typical scenario is that the thief starts off with stealing a small amount. The boss thinks that it is not worth sending his staff for polygraph tests. He tries to improve his control measures. The thief gets bolder and eventually ends up stealing a huge amount and also getting other staff involved. At the same time, they create alibis to blame their crimes on innocent people. Unfortunately, many of our clients come to us for help only after they are hit hard and after the police failed to solve their earlier cases. After solving the cases for them, clients often tell us that they should have come to us earlier.

    There is a saying that humans are inherently greedy animals and our hunger knows no bounds. Studies have shown that employee theft in retail businesses are rampant despite security measures like CCTV cameras and other control measures. In the US, over 50 billion dollars are lost each year to employee theft. 75% of employees stole at least once during their careers and at least half of these 75% stole multiple times. With the increasing reliance on computer technology and the Internet, computer crime has become a major concern among large corporations and law enforcement agencies. Security systems, internal controls and audits are not fool-proof to prevent computer and other workplace crimes like theft, fraud, corruption, collusion with vendors / suppliers, sabotage, theft of corporate or state secrets etc.  Clearly, many business cannot continue to function in the face of such losses.

    Spy Scandals: Security and intelligence agencies in advanced countries use it for counter-espionage screening after they are plagued by spy scandals. In Taiwan, high level spy scandals in recent years have resulted in the increase in usuage of the polygraph for periodic screening.

    Massive Employee Fraud: From time to time, one learns from the media about massive accumulated financial losses suffered by organisations as a result of employee theft, which went undetected for long periods of time.  Most of these crimes are detected by accident. It is more and more apparent that cybercrime, money laundering, corporate fraud are becoming a real growth industry of the 21st century. Singapore is reputed to be among the top few least corrupt countries, but look at these following cases. In the last few years, numerous local and foreign banks in Singapore fell victims to theft of millions of dollars by their own staff.  In 2000, an airline staff in Singapore was convicted of embezzling a staggering sum of $35m over 13 years. In Singapore's largest case of commercial fraud, a senior staff of a local brewery was convicted in 2004 of swindling 4 foreign banks of $114m over a four-year period. In 1995, a deputy chief executive at the Public Utilities Board was jailed for 14 years after he was convicted for taking $13.9 million in kickbacks in Singapore's largest graft case. In June 2010, the Singapore Land Authority was hit by a $12 million fraud case involving 2 of its senior staff. In 2014, an Assistant Director of the Corrupt Practices Investigation Bureau was convicted of misappropriating $1.76 million.

    Bunker Corruption: The bunkering industry is particularly vulnerable to corruption. In late 2001, bunker surveyors from more than a dozen Singapore companies were convicted of corruption. The bunker surveyors were bribed to overstate the quantity and / or quality of fuel supplied to vessels by employees of fuel suppliers. Since then, Polygraph Investigative Services have been retained by Maritime and Port Authority of Singapore (MPA) accredited bunker survey companies and ship charterers to conduct independent polygraph tests on surveyors, cargo officers, vessel Chief Engineers etc whenever there are significant disputes over the figures or where corruption is suspected. Clients from Singapore, Malaysia, Switzerland and the Middle East, including UAE have sought our services to conduct such lie detector tests in our Singapore office as well as on board vessels berthed in foreign countries like Australia.

    Corruption In Sports: In Singapore, the well-publicised case of the Football Association of Singapore using polygraph screening of players and match officials in the S-League to detect or deter corruption, is an example of this application. A similar match-fixing scandal in South Korea's K-League uncovered in June 2011 involving top players resulted in the use of polygraph testing.

    Time To Be Proactive: Corporate fraud can strike any company, anytime. Contrary to popular belief, corporate fraud happens to good companies and effective managers. Our decades of experience in polygraph personnel screening provides organisations with an effective proactive means to detect and/or deter such crimes. Through in-service polygraph testing, we help businesses identify the dishonest employees and also find out how much they have stolen so that corrective action can be taken. The pull of money is just too great. Experience has taught us that most people will steal if they think that they can get away with it. For many companies the time to act is now; for some, now is too late.

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Can Nervousness Cause An Innocent Person To "Fail" The Test?

    It is quite common for an examinee, whether innocent or guilty, to feel nervous during a polygraph test, especially if it is the first experience. It is no different from a job interview or taking a school examination. When administered by a competent and experienced examiner, nervouness should make no difference to the test. Their are certain testing protocols built into the process to take care of nervousness.

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Will The Results Be Affected If The Examinee Knows The Technique? Can Such A Person Beat The Test?

    No, there is no effect on the test results even if an examinee knows the technique, if the test is conducted by a competent examinee. Over the years, we have conducted many lie detector tests on subjects who were trained in the technique and the results turned out to be no different from an ordinary man on the street.

    There is one or two anti-polygraph personalities from the United States spreading misinformation on the Internet, claiming to be able to teach a guilty person to 'beat the test'. They make a living out of it. Such attempts are amateurish and do not work.

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Are Polygraph Tests Meant For Criminals?

    No, polygraph examinations are meant for people from all walks of life. We have examinees ranging from suspects / accused involved in investigations to senior employees, CEOs and Superscale Officers who are screened for promotions and routine in-service screening. In fact the large majority of examinees who turned up at our office "passed" their tests.

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Brain Fingerprinting Test

    In a brain fingerprinting test, which is sometimes known as brain mapping, words, pictures or sounds describing salient features of a crime, terrorist act or terrorist training are presented by a computer, along with other, irrelevant information, that would be equally plausible for an innocent subject. Items are chosen that would be known only to the perpetrator and to investigators, but not to the public or to an innocent suspect. The subject is told which features he will see (e.g., the murder weapon), but is not told which item is correct (e. g, gun, knife, or baseball bat). When a subject recognises something as significant in the current context, the brain emits a specific brain response known as the P300 brainwave. If the record of the crime, terrorist act or terrorist training is stored in the subject's brain, this response appears when the subject recognises the correct, relevant items. If not, then the response is absent. The results are not affected by the willingness of the person being tested to tell the truth. The recognition of specific information from the crime scene, terrorist training or of individuals at a training camp can be detected. Therefore, investigators must have reliable, factual details from which to draw the information that will be used to structure the Brain Fingerprinting test.   A computerized mathematical analysis of the data determines whether or not the subject has knowledge of the salient details of the crime, terrorist act or terrorist training.

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How Do I Follow-up To Book A Polygraph Test?

    Booking a polygraph test is easy. After you have decided to proceed with the polygraph test, contact us and arrange an appropriate time for the test which takes about 2 - 2.5 hours, either in the morning or afternoon. For non-regular clients, you will need to come to our office to place a deposit. If you are in a foreign country, payment can be made via telegraphic transfer. Before the test, we will require the full facts of your case for preparation purposes. You can email or fax the facts to us or to present it in person. You can suggest the case related test questions which are usually limited to 3 or 4. These questions must be short, direct, unambiguous requiring a 'yes' or 'no' answer. On the day of the test, please bring along your cash payment in full. We only accept cheque payment from corporate clients. If you are on medication, you should take your prescribled medicine before coming. Please come on time. We give a maximum of half an hour grace period before awarding the time slot to another client. Many of our foreign clients require polygraph tests to be conducted in their respective countries, especially when there is a group to be tested. This can be easily arranged. We give special bulk discounts to offset the additional cost incurred by airfare and accommodation. Simple as that!

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