What is a polygraph examination?
A polygraph or a “lie detector test” is the method used by police or private examiners to determine whether someone is telling the truth or telling a lie. The word polygraph comes from the Greek words “poly” and “graphos” which means “many writings” and is comprised of the various components used during the test. 

What does the polygraph do?
Basically, the polygraph instrument, once put onto the examinee’s body will record physiological responses and transmit these responses to the examiner’s computer monitor. From the beginning of the test to the end of the test, your body is emitting physiological data that will be later reviewed by the polygraph examiner to determine if the examinee was telling a truth or telling a lie. There is no light or sound that the computer makes to indicate truthfulness or deception during the test. 

Can someone force me to take a polygraph examination?
Absolutely not! You must voluntarily agree to take a polygraph test and without threat. If you are uncomfortable at any point during the test you can leave anytime you wish. 

How long does a polygraph examination usually take?
This depends on the examiner and the type of test conducted, but typically a test can last anywhere between 1.5-4 hours. Shorter tests are typically re-tests and longer tests tend to be legal or forensic cases where multiple tests need to occur or more information needs to be discussed prior to the start of the test.

Whose side is the examiner on?
Neither! A polygraph examiner is a neutral third-party person whose main objective is to determine if the examinee is telling the truth or telling a lie and report these results. Every person whether truthful or not, has the right to be examined with dignity and impartiality. 
 
What is the accuracy of a polygraph examination?
In a meta analysis published in 2012 to the American Polygraph Association, all polygraph formats were evaluated to determine their validity and accuracy in assessing truthfulness and deception. It is important to keep in mind that polygraph is a scientific field and will never be 100% accurate, even condoms and birth control are not 100% accurate! With a single-issue test, a test that focuses on one event or issue, uses three questions, and uses the proper scoring method has an accuracy of about 92%. With a multi-issue test, a test that focuses on multiple events or issues, uses four questions, and uses the proper scoring method has an accuracy of about 84%. I typically recommend examinees opt for the single-issue test as they have a higher accuracy. Additionally, inter-rater reliability, scores calculated by different examiners on the same data, fall around 98%. This is because examiners in Canada are trained the same way, they use the same test format, and the same scoring technique. 

Will I know beforehand what the test questions will be?
Yes. Before the polygraph examination is even conducted you will know all the questions that will be on the test and all the answers will be either yes or no. We are not trying to shock you on a polygraph test with questions you have never heard before, this is not the reaction we are looking for. Instead, we want to see if you are telling the truth or telling a lie on the test. 

What can be tested on a polygraph examination?

Only questions regarding actions and events can be asked on a polygraph examination. I am not able to test on questions regarding thoughts, emotions, feelings, intentions, or love.  The reason for this is because actions or events are concrete things, whereas thoughts, emotions, feelings, intentions, and love are abstract concepts and very difficult to define and can change at any point in time. 

How do I prepare for a polygraph examination?
Eat before you come to an appointment, an appointment can typically last between 2-3 hours. Bring water to the appointment, there will be a lot of talking and you may get thirsty. Think about why you are pursing a polygraph examination, what is the big issue you want to address? Take any prescription medication as directed by your doctor, try not to alter your routine before coming to the test. Try to get a full night’s worth of sleep so you are not tired during the test. Do not have any fights or arguments about the main issue within 24 hours of the start of the test, it is emotionally exhausting for the examinee and could interfere with sleep, meals, and overall wellbeing. 

I am nervous about taking a polygraph examination, will this affect my results?
No. You can be as nervous as you like on a polygraph examination as we do not measure nervousness. Typically, clients feel more comfortable by the time the test starts and usually they report that they are no longer nervous. Nervousness and deception look different on a polygraph chart and a polygraph examiner is trained to distinguish between the two of them. You can be as nervous as you like on a polygraph test as this will not affect the results.

I feel some sort of trauma attached to why I am taking a polygraph test, will this affect the results?
If you feel some sort of trauma regarding the content of a polygraph test you probably should not be taking the test. Some topics are hard for some people to face and they need more time to process the events before they can take a polygraph test, and this is okay. No one can be forced to take a polygraph test and I would suggest talking to a psychiatrist, psychologist, psychotherapist, or social worker if you feel this is a better option. An examiner does not want to put an examinee into position where they could be triggered.

I have a medical condition, could this affect the polygraph examination?
Sometimes. The polygraph examiner will conduct a background form to assess the mental and physical condition of the examinee prior to the test to determine suitability. Assessing suitability is very important as some individuals may not be fit to take a polygraph test based on their mental state, medical condition, or medications. Suitability is determined on a case by case basis. It is very important to be 100% honest with the examiner when disclosing your mental and physical history. Some reasons an examinee would be deemed unsuitable to take a polygraph examination are included but not limited to being under the influence of drugs or alcohol, in a state of distress, or not consistently taking any prescribed medication. If a polygraph examiner deems an individual to not be suitable to take a test this decision is final. 

Will I receive an electric shock on a polygraph test?
Absolutely not! There is not electrical shock that is administered with a polygraph test. 

How does a polygraph machine work?
A polygraph is made up of five components which include two pneumo tubes, a blood pressure cuff, a vasomotor response indicator, electrodermal activity plates, and a motion sensor pad. All components are placed on the examinee’s body for the polygraph examination and transmit physiological reactions. Each component is very sensitive to bodily changes.

Is a polygraph test comfortable?
For the most part yes, unfortunately some people feel slight discomfort with the blood pressure cuff that is placed around the arm. The blood pressure cuff is the same instrument that you see at the doctor’s office and is used for the same purpose. Some people find the cuff to be uncomfortable when it is inflated but it does not cause any harm. 

What happens if a piece of equipment malfunctions during the examination?
It is obvious to an examiner if a piece of equipment has malfunctioned during the test. The examiner will immediately stop the test and fix any components to ensure that the polygraph is functioning correctly again. It is extremely important that an examiner have the most amount of strong data to analyze after the test and malfunctioning equipment severely impedes this. 

What if someone is trying to deliberately manipulate the test?
Do not do this! It is obvious to a polygraph examiner what you are trying to do, and the test will be terminated immediately. This is a huge waste of time and money for the examinee and the examiner.

How do I pass a polygraph examination?
You cannot “pass” a polygraph examination, instead you will be found to be truthful, deceptive, or inconclusive on a polygraph. To be the best polygraph examinee in a polygraph examination please follow all the instructions provided by the examiner, tell the whole truth, and participate in the process. 

Will a polygraph test find me guilty or innocent?
We do not use this language here in Canadian. In the US, the polygraph is used as an investigative tool and you are found innocent or guilty based on the results of the test. However, in Canada we use a polygraph examination as a confirmation test, meaning we are either confirming or not confirming your statement of fact for why you are taking a polygraph. Therefore, the results will be deception indicated (you are telling a lie), no deception indicated (you are telling the truth), or inconclusive (data is insufficient for analysis).

What does it mean to score an inconclusive on a polygraph examination?
An inconclusive on a polygraph test can occur due to a couple of reasons. The first, and most problematic, is that the examinee is purposefully not cooperating with the examiner’s instructions. Typically, polygraph instructions will direct the examinee to sit still, let your body do it’s natural thing, and to answer every question with either yes or no. Moving around on the test or answering the questions wrong makes the charts messy and hard to read which leads to an inconclusive score as the examiner is not able to score the charts. Another reason someone could score inconclusive on a test is something called psychological defense mechanisms. These are psychological barriers you think of to protect yourself. If you have ever heard a politician speak or watched a political debate you know of some verbal loopholes that some people say to circumvent admitting the truth. This is problematic in a polygraph as the examinee and the examiner must be on the same page when it comes to coming up with the best questions to ask on the test and have the same understanding of the words being used. Make yourself very clear to the examiner and be forthcoming with important information. Lastly, a person may score inconclusive on a polygraph examination due to telling half-truths. Withholding some pieces of the story can cause turmoil within the examinee and during the test this constant battle of which information they want to disclose could cause the examinee to score inconclusive or even deceptive because they know they are not being 100% truthful to the examiner.