FAQs About The Polygraph

Background Information - What is a polygraph?

   The polygraph test, known popularly as “lie detection” has been in use in the United States for almost a hundred years.  Over the last few decades, polygraph tests have proven to be one of the most powerful, robust and useful scientific tools in criminal investigations and personnel screening.  It is routinely used in almost all major investigations in advanced countries employing this forensic tool. 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 personnel screening.  There is also widespread use of polygraph testing in spouse infidelity and relationship issues. Today, the polygraph test is used in more than 56 other countries world-wide, including Australia, Canada, China, Japan, Israel, Malaysia, Mexico, Philippines, Romania, Russia, Singapore, South Korea, Taiwan, South Africa, 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.

Polygraph Applications Overview

   In Singapore, since it was first introduced in 1977, polygraph tests have gained widespread use - in practically all government law enforcement, 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. Since the establishment of Polygraph Investigative Services, a government-licensed private company in 2001, local as well as regional private companies have engaged its polygraph testing services to help solve difficult workplace crimes and screen employees. We do extensive polygraph employee screening for retail businesses as well as manufacturing industries where, despite tight security measures, theft by employees are rampant. 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 Malaysia, Indonesia, China, India, Hong Kong, Thailand and Brunei. These polygraph tests were carried out locally in Singapore as well as in foreign countries. Defence lawyers have also sent their clients for polygraph tests to help in their defence, mitigation and making representations to the Attorney General's Chambers.

How Does the Polygraph Test Work?

    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.

How Accurate is the Polygraph Test?

    There are now about 25 research studies available on the accuracy of the polygraph 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 competent examiner to be about 90%.  Level of skill 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.

     The polygraph test is often wrongly portrayed as a "lie detector". Nothing is further from the truth. What the polygraph does is - it records changes in the subject's stress level as manifested in his or her respiration, Galvanic Skin Resistance and cardiovascular activity when asked a series of test questions comprising control, relevant and and irrelevant questions. The polygraph does not detect lies. In fact, its function is very similar to that of an x-ray machine - it does not detect illnesses. The polygraph examiner carefully studies all available case data and physiological data collected and make an assessment of the subject's truthfulness, deception or an inconclusive result. The process is highly complex and the accuracy of the test is dependent on the skill and experience of the examiner. The process is quite similar to how a doctor or surgeon makes a medical diagnosis. Hence it is erroneous to generalise and say whether the polygraph is reliable or unreliable. Rather, it should be whether the particular polygraph examiner carrying out the test is reliable or unreliable.

Is Polygraph Test Evidence Admissible in Court?

    Although the polygraph test has been in use in the United States for almost a hundred years, this technique is relatively new in the Asia Pacific region.  There is no court ruling on the admissibility of polygraph evidence in most of these countries, including Singapore.  In Japan, 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.

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 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.  Investigative resources can then be focussed on gathering evidence on the culprit.  Many a times, this leads to the guilty confessing his crime through skilful interviewing or interrogation.

    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.

For More News On Actual Cases Handled by Polygraph Investigative Services ...

    - One Million Dollar Theft of Platinum...
    - The Golden Rooster Case...
    - Syndicated Theft At A Manufacturing Plant...

Why Use Polygraph for Personnel Screening?

Polygraph Pre-employment Screening

   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. Consequently, some individuals are hired who eventually put the employer, co-workers, and members of the public at risk because of their inappropriate behaviour.  Conventional screening methods like interviewing, checking with characters referees and past employers are inadequate, especially for positions of trust.  Furthermore, conventional methods cannot be used to screen foreign employees.  Even for organisations with access to criminal and other official records, they find that such records are inadequate.  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, 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.

    With heightened security as a result of the September 11 attack, it is even more compelling for organisations, which are potential targets to consider polygraph screening to guard against infiltration or sabotage. The killings of 12 army personnel at Fort Hood, Texas (CNN report dated 7 November 2009) and 7 CIA and one Jordanian operatives at the hands of a terrorist double agent at a US base in Khost, Afghanistan (CNN report dated 5 January 2010), and the botched attack on an airliner bound for Detroit (CNN report dated 27 December 2009) continues to highlight the increased sophistication of the adversaries and the limitations of intelligence gathering and "connecting the dots". The greater use of the friendly polygraph in personnel screening as a complement other methods, would have increased the effectiveness many fold in pre-empting such incidents.

Polygraph Investigative Services looks into the different requirements of individual clients and develop customised screening programmes to meet individual needs.

Periodic Polygraph Employee Screening

   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.  Security and intelligence agencies in advanced countries use it for counter-espionage screening.  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. 

    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. Clearly, many business cannot continue to function in the face of such losses.

    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 corporate fraud is becoming a real growth industry of the 21st century. In the last few years, numerous local and foreign banks in Singapore fell victims to theft of milions of dollars by their own staff.  In late 2001, bunker surveyors from more than a dozen Singapore companies were convicted of corruption. 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 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.

    Corporate fraud can strike to 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. For many companies the time to act is now; for some, now is too late.

Does Nervousness Cause A 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.

Are Polygraph Examinations 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 and CEOs who are screened for promotions. In fact the large majority of examinees who turned up at our office "passed" their tests.

Brain Fingerprinting Test

   In a brain fingerprinting test, 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.