FREQUENTLY ASKED QUESTIONS
WHAT IS A POLYGRAPH?
The term “polygraph” means “many writings.” The name refers to the manner in which selected physiological activities are simultaneously collected and recorded. The polygraph is like a recorder, except instead of recording sounds, the polygraph instrument will record physiological changes occurring within the examinee's body as the polygraph examiner asks a series of test questions. The polygraph instrument is basically a combination of medical devices that are used to monitor changes occurring within the examinee's body. As an examinee is questioned about a certain event or incident, the examiner records and monitors the relative changes in the examinee’s heart rate, blood pressure, respiratory rate, and electro-dermal activities.
Source: Lafayette InstrumentsThe polygraph instrument has undergone a dramatic change in the last decade. For many years, polygraphs were those instruments you saw in the movies with little needles scribbling lines on a single strip of scrolling paper. These are called analog polygraphs. Today, many polygraph tests are administered using digital computerized equipment. The scrolling paper has been replaced with sophisticated algorithms and computer monitors. Hobson’s Polygraph Service uses a Lafayette Computerized Polygraph Instrument – both in a desktop model for polygraph examinations administered in the office and in a laptop model for travel as pictured below.
Source: Lafayette InstrumentsPolygraph examinations are most often associated with criminal investigations, but there are also a number of other uses for the polygraph. One day you may be subjected to a pre-employment polygraph examination before being hired for a job. Today, many government entities and law enforcement agencies require a pre-employment polygraph screening in conjunction with the background investigation prior to employment.
Source: Lafayette InstrumentsRelative physiological changes within the examinee’s body are monitored by the following polygraph attachments:
Respiratory rate: Two rubber tubes filled with air, called pneumographs, are placed around the examinee’s chest and abdomen. When the chest or abdominal muscles expand, the air inside the tubes is displaced. The digital or computerized polygraph employs transducers to convert the energy of the displaced air into electronic signals.
Blood pressure/heart rate: A blood pressure cuff is placed around the examinee’s upper arm. Tubing runs from the cuff to the polygraph. Again, in digital or computerized polygraphs, these signals are converted into electrical signals by transducers.
Galvanic skin resistance: This is also called electro-dermal activity and is basically a measure of sweat on your fingertips. The fingertips are one of the most porous areas on the body and therefore are a good place to look for sweat. The theory is we sweat more when we are placed under stress. Fingerplates, called galvanometers, are attached to two of the examinee’s fingers. These plates measure the skin’s ability to conduct electricity. When the skin is hydrated (as with sweat), it conducts electricity much more easily that when it is dry.
The polygraph examination involves three phases: The pre-test phase, the data collection phase, and the data analysis phase.
In the pre-test phase the polygraph examiner will complete the required paperwork and then familiarize the examinee with the testing procedure and the polygraph instrument. He will spend most of the pre-test phase discussing the issue for the polygraph test. Before the examinee is attached to the polygraph instrument the examiner will review each polygraph test question with him, word for word. There are no surprise or trick test questions.
During the data collection phase the examiner will administer the polygraph test and collect a number of polygraph charts depicting physiological changes occurring with the examinee’s body as the examiner reads each test question and the examinee answers “yes” or “no.”
During the data analysis phase, the examiner will carefully review and score each chart in order to render an opinion as to the truthfulness of the examinee’s answers. The opinion rendered will be one of the following: No Deception Indicated meaning the examinee answered the relevant questions truthfully, Deception Indicated meaning the examinee did not tell the truth to the relevant test questions, or sometimes the opinion is Inconclusive when the examiner is unable to determine truth or deception from the examinee’s polygraph charts due to abnormal and/or inconsistent physiological reactions.
If the examinee renders an opinion of Deception Indicated, the examinee is given the opportunity to explain his deceptive physiological responses as displayed on his polygraph charts.
WHO USES POLYGRAPH TESTING?
The three segments of society that use the polygraph include law enforcement agencies, the legal community, and the private sector.
They are further described as follows:
Law Enforcement Agencies – Federal Law Enforcement Agencies, State Law Enforcement Agencies, and Local Law Enforcement Agencies such as the police and Sheriff Departments.
Legal Community – U.S. Attorney Offices, District Attorney Offices, Public Defender Offices, Defense Attorneys, Parole Agencies, and Probation Departments.
Private Sector – Companies and Corporations under the restrictions and limitations of the Employee Polygraph Protection Act of 1988 (EPPA), private citizens in matters not involving the legal or criminal justice system, and attorneys in civil litigation.
POLYGRAPH SCREENING IN POLICE AGENCIESThe Employee Polygraph Protection Act of 1988 (EPPA) prohibits most private employers from using polygraph testing to screen applicants for employment. It does not affect public employers such as police agencies or other governmental institutions.
In 1988, there was no current and reliable data on police applicant screening. The APA Research Center at Michigan State University embarked on a survey of police executives in the U.S. to determine the extent of, and conditions in which, polygraph testing is being used for pre-employment screening. The survey population included 700 of the largest police agencies in the United States, excluding federal agencies, and produced usable returns from 626 agencies, a response rate of 90%. The major results of the survey showed the following:
Among the respondents, 62% had an active polygraph screening program, 31% did not, and 7% had discontinued polygraph screening, usually because of prohibitive cost factors.
These results make it clear that a great majority of our largest police agencies do have a polygraph screening program in effect. These agencies employ, on average, 477 officers and service a population averaging 522,000 citizens. They primarily use the polygraph to screen applicants for sworn positions, although 54% also screen persons interested in non-sworn positions. Approximately 25% of the persons tested are disqualified from police employment based on the information developed during polygraph testing which, by the way, is used both to verify information provided in an application form and to develop information that cannot be gotten by other means.
Only a very small proportion (2%) of agencies use polygraph testing as a substitute for a background investigation. A rank ordered listing of topics covered during polygraph testing revealed that investigation of illegal drug usage, employment related dishonesty, and involvement in undetected criminal activities are the most important.
When asked to indicate what their reasons were for using polygraph screening, the great majority of the agencies indicated the polygraph test reveals information that cannot be obtained by other selection methods. Closely following this item in order, was polygraph testing makes it easier to establish background information, it deters undesirable applicants, and it’s faster than other methods of selection.
The three leading benefits of polygraph screening were that job applications were more honestly completed; higher quality employees were hired; and there were fewer undesirable employees.
Over 90% of these agencies expressed either moderate or high confidence in their polygraph screening program and 80% of them reported that in their experience the accuracy of the testing ranged between 86% and 98%. The only procedure that was considered to be as useful as polygraph screening was a background investigation; all others, including written psychological test, psychological or psychiatric interviews, personal interviews, and interviews by a selection board were judged to be less useful.
Finally, this survey also showed polygraph screening revealed the applicant’s involvement in serious, undetected criminality. For example, 9% of the agencies said polygraph screening detected involvement by some applicants in unsolved homicides; 34% indicated some applicant involvement in forcible rape; and 38% showed some applicant participation in armed robberies. Other serious, unsolved crimes, such as burglary, arson, and drug offenses were also revealed by polygraph testing.
WHAT POLYGRAPH QUALIFICATIONS ARE IMPORTANT?
There are approximately 3,500 polygraph examiners in the United States. According to Frank Horvath, a Michigan State University professor of criminal justice, approximately 2,000 of these polygraph examiners belong to a professional organization.
Frank Horvath, a member of the American Polygraph Association, is concerned about the credentials and qualifications of many polygraph examiners who do not belong to some sort of professional organization. Laws regarding polygraph licensing vary from state to state and there is no government or private entity that controls polygraph licensing. Horvath also feels the training of polygraph examiners is inadequate. According to Horvath, you could buy a polygraph instrument tomorrow and come to Michigan and you wouldn’t be able to administer polygraph examinations because the state of Michigan has a rigorous polygraph licensing law, but you could move down to California or any number of other states, and open a polygraph business tomorrow.
Less than half the states in the U.S. have a polygraph licensing law and unfortunately, California is one of them. Therefore, the qualified, trained, and experienced examiners in California rely on polygraph certification through their state and national polygraph associations.
The results of your polygraph test may change your life. Make sure you have the test performed by the best polygraph examiner you can find. When choosing a polygraph examiner the price of the test is the last thing you should ask about; affordability does not always equal quality. Remember the saying, “You get what you pay for.” Don’t put yourself in the hands of anyone but a highly trained and qualified professional. When selecting a polygraph examiner to conduct your polygraph test, inquire into the following areas involving experience, training, and qualifications:
The polygraph examiner should have completed a nationally recognized and accredited polygraph school which normally takes between 8 to 10 weeks to complete. After completing the polygraph school, the new polygraph examiner conducts polygraph examinations during an “internship” period. During this period the polygraph school reviews the examiner’s work and if his work meets the school standards, the polygraph examiner is awarded a certificate of completion. In California, after receiving the certificate of completion the examiner should apply for membership in the state polygraph organization called CAPE (California Association of Polygraph Examiners). The examiner may also apply for membership in a national polygraph association. The two most prominent national associations are the APA (American Polygraph Association) and the AAPP (American Association of Police Polygraphers). These associations provide polygraph examiners with advanced training and continuing education courses in order for them to maintain their proficiency. Based on the total number of continuing education hours completed within a two year time period, determine whether the polygraph examiner has been CERTIFIED by the California Polygraph Association (CAPE) and/or the National Polygraph Associations (AAPP and APA). Beware of polygraph examiners who boast about their years of training and experience, yet they have not completed any advanced training or continuing education courses in years. Technology changes through the years and polygraph examiners must keep up with these changes. Was the polygraph examiner employed by a county, city, state, or federal law enforcement agency? How many examinations has he or she conducted? How many were criminal specific issue examinations as compared to pre-employment screening examinations? This is important because law enforcement polygraph examiners also have years of training and experience in interview and interrogation techniques and other related training that enhances their proficiency in obtaining admissions and confessions from those examinees whose test result shows deception to the relevant test questions. Make sure the polygraph examiner you select has training and experience in the type of polygraph examination you’re looking for. If the polygraph examiner does not have this training and experience or is unable to provide you with answer to these questions, that polygraph examiner may not be a good choice. Again remember, you get exactly what you pay for.
WHY ARE POLYGRAPH EXAMINATIONS EXPENSIVE?
The best polygraph examiners are highly trained and experienced professionals with a college degree. These polygraph examiners provide a very specialized service. This service requires the examiner to purchase very expensive equipment and pursue continuing education in order to maintain the highest degree of proficiency. The time required to conduct a specific incident “single issue exam” averages between three and four hours. In most cases, the polygraph exam is conducted because there simply is no other reasonable way to get the desired information, such as when no evidence exists one way or the other, or when it is simply a “he-said-she-said” situation. For example, in a fidelity case a person might spend thousands of dollars on continuing surveillance while the same information could be obtained for a fraction of that price with a polygraph test and thereby save thousands of dollars. The fees charged for polygraph examinations are reasonable when considering the cost of the polygraph examiner’s training, the equipment required to do the job, the degree of specialization, and the worldwide need for this unusual service.
HOW ACCURATE IS A POLYGRAPH TEST?
The current polygraph research indicates that when a specific single issue polygraph exam, conducted by a qualified, trained, and experienced polygraph examiner, is properly administered the accuracy rate is between 95% and 98%. This percentage is still higher than other forms of evidence, including psychiatric opinions, suspect identification as provided by victims and witnesses, and fingerprint identification. The polygraph is the most accurate tool available today for determining truth or deception. The accuracy of the multi-issue exam drops in accuracy due to a number of psychological factors. These statistics do no include “inconclusive” test results in which no opinion of truth of deception can be made from the physiological data collected on the polygraph charts.
WHAT KIND OF QUESTIONS MAY BE ASKED ON A POLYGRAPH TEST?
Normally, eight to ten questions are asked on a polygraph test. Prior to administering the test, all test questions are reviewed with the examinee, word for word. The question review process eliminates any misunderstandings, confusion, or attempts to rationalize the true meaning of any test question. There are no surprise or trick questions. The test series consists of relevant questions interspersed with irrelevant and comparison questions.
The answer to each test questions is limited to either a yes or no. There are no narrative answers or interrogation taking place during the polygraph test as portrayed on television or in the movies. Compound test questions or test questions that ask for opinions, feelings, emotions, intent, or frame of mind must not be used. Hypothetical questions or questions about future events must not be used. If your question was not answered in the FAQs listed above, please Click Here, complete the form and ask your question. Larry Hobson will respond with an answer to your question in a timely fashion.
