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Part 7 - The Polygraph Examination

Deputy Bob Cooley

The polygraph or lie detector examination is right up there in anxiety levels as the pre-employment interview. All kinds of questions roll around in the applicant’s head as to what the polygraph examiner might ask. When I took the very first polygraph I felt the same way. I had visions of the examiner going all the way back deep into my childhood to drag to the light transgressions committed when I was ten years old. I’m not going to sit here and tell you I was an angel, but I can truthfully say I wasn’t “Damien” from the “Omen” series of movies either.

The polygraph is an electro-mechanical device also known as a lie detector used to determine whether an examinee is truthfully answering questions. It simultaneously measures and records certain physiological changes in the human body, which it is believed, are involuntarily caused by an examinee’s conscious attempt to deceive an interrogator (Black’s Law Dictionary 1990).

The examination is conducted by a trained and certified operator who has a list of questions, which will be asked during the test. He or she will ask the questions beforehand and record in writing your responses to those questions. From that question pool the examiner will ask you the questions both he or she believes are important to the examination as well as questions required by the agency. Usually the operator/examiner will take an applicant through the test three times in order to establish a baseline for the applicants physiological state and then twice more for the purpose of detecting deception.

First, please do not take any medication unless your doctor prescribes it. Cold medications, cough syrup and other over the counter remedies can have an adverse affect on your polygraph results. Every polygraph examiner I have ever dealt with has asked as one of the first questions whether or not I had taken any form of medication or alcohol. So unless you have a bad cold or the flu don’t take anything! If you are sick enough to take medication you might want to consider asking for a change in date for the test.

Second, come for the test dressed in comfortable cloths, but again as I pointed out in the pre-employment interview section wear clothing that will reflect favorably upon you.

Third, listen carefully to the questions from the examiner before you answer. This applies to the pre-test and the actual examinations. You don’t want any misunderstanding to occur between you and the examiner by misinterpreting a question.

Fourth, relax you will not be hit by a jolt of electricity caused by the machine so try to stay as calm as possible during the examination. The examiner will give you a chance to take a break between tests so sit back take a deep breath.

Continue To Part 8: The Physical Examination

  • Images_max50


    about 5 years ago


    Wow sorry there Nancym that really sucks. But I bet the next time you apply you will get even closer if not hired. I have been passed up by a few departments and I know how you feel. What sucks even more is not knowing why they passed you up. Maybe you soon to be ex had a few not so nice things to say about you, or maybe the department didn't want to take a risk of you being around drugs at the time you were applying. I have a friend that I work with right now that applied to another department and passed the written, physical, background, oral, poly, police chief interview, and got all the way up to having a sit down with the mayor of the city. It was less than a week before he was suppose to be sworn in and he got a letter in the mail saying sorry we have changed our minds. There's no telling what makes them decide something like that, maybe they called an old boss and caught him on a bad day, or maybe they had to choose one of two applicants and the one with a speeding ticket got dropped. Who knows, but the next time you apply don't change your answers!!

  • M_47410fdb0048b0ac6cdb0d27962cc918_max50


    over 5 years ago


    I took a poly it took 3 hours to complete. My problem became apparent to me that when I answer truthfully I have never done drugs but was in the process of a divorce because I learned my spouse did drugs it seems that having that knowledge hurt my answer. At the end of the interview the interviewer told he believes me when I said I have never done drugs but when ever I was hinted towards my spuse of use I guess my nerves would jump or something. The way I saw it I was relieved to tell someone yes my spuse does drugs and since I am so agaist it I am living him.

    A few days later I got a letter stating we have decided not to continue on processing your application.

    What the heck is that suppose to mean

    call us back once your divorce?

    I would have prefered to be given a reason of why I was being pass over.
    Since I know the interviwer belived I answer all of the questions asked truthfully.

    I even had an oral board interview of 3 police officers or detective before I took the poly

    I just don't understand?

    I know I have meet all of the qualification.

    Pass the CJABAT
    Background check
    Have Military under my belt
    BA in Criminal Justice Admin.
    Fluent in English and Spanish
    Good moral, conduct values.

    Well I have decided to just pay for the academy myself did my own background check acquire my own driving/ criminal reporst so all I have to due is turn it in and all the department who decides to work with if they are interested is double check my history, in Hopes that this would speed things up. Hopefully I can pass over a lot of the steps that are time consuming when one is trying to be hired by a department and be send to school.

  • Ghostrider_02_1024x768_max50


    about 6 years ago


    I'm just wondering, I completed mine and it came back inconclusive. The examiner basically did a two hour interogation accusing me of lying and telling me that he had proof from another department that I was lying to him. When I told him that it was not true he finaly admitted that it wasn't a crime the other department had said I was involved in but rather it was a report I had filed with the agency on behalf of an employer I worked security for. By the time this was all finished I was so upset about being blamed for things I had not done that I could not relax during the exam. Then he told me that my test was inconclusive because he had seen me continually twitch my finger during the test (which I was completely unaware of) and said that I had obviously been researching polygraphs on the internet to learn these "tricks." Needless to say I'm very disappointed because I told the truth and don't think I got a fair shake. Any thoughts or advice would be appreciated. I'm just completely floored.

  • Justice-400_max50


    about 6 years ago


    Just to add:

    He's very right about wearing comfortable clothes. Don't come in a suit.
    Eat a big breakfast.
    Get a full night's sleep.

    I did a poly on five hours of sleep broken up (worked the night before) in a suit, having only eaten a granola bar. Even when I told the truth on every question I failed two of them. Three days later, I took another with a different agency I was testing with. I got seven and a half hours of sleep, ate eggs and toast for breakfast, and then went to the poly in business casual clothing. The examiner basically told me after only running through the questions twice that, "It couldn't have gone better." These things make a big difference.

  • West_coast_max50


    about 6 years ago


    Thanks, good info

  • Photo_user_banned_big


    almost 7 years ago


    good to know

  • Photo_user_banned_big


    almost 7 years ago


    good stuff!

  • 128846014394059542_max50


    about 7 years ago


    Folks please do not post your questions here, post them in "Law Enforcement Careers." Your questions will be answered there.

  • Pic11_max50


    over 7 years ago


    I neer knew they give you a poly test. The things I am learning.

  • Photo_2006_8_20_2_24_10_max50


    over 7 years ago


    First of all , the examiner will ask all questions in a pre-test, then he will ask you the same questions again. this is not to trick you, its to gage your responses. He will ask things like "have you ever tried drugs." Don't let them bother you with this. Ask what do you mean, illegal, narcotic, or what? if you have taken drugs you must tell them. Know what your department expects. Some will drop you like a hot potato if you have even smoked weed back in high school. Ask what the policy is, if you had a joint on the way to the test chances are your not going to pass. They are very sensitive and you don't have to "fail" the test to fail the background investigation. If he thinks that you are being decietful that does not mean a lie, just maybe he can't tell, or its inconclusive, guess what? Your out and there is no debate about it, the background investigator has lots of work to do and not much time to get it all done, he is going to send you a thank you, no thank you letter in the mail.
    Talk with the examiner, make sure you understand the question and ask him what he means by it. Tell him what you have done and then when his does the test he will say, " other than what we have talked about, is there any other drug use in your history. if you were honest in the pre test you will pass the Poly with flying colors.
    They often ask questions like "is there anything in your driving record that you are concerned about?" I had to ask my guy about every question, it took him two hours longer with me than he had spent with any other canidate, don't rush this one, take your time, make him take his time. most of all relax.

  • 0219081646_max50


    over 7 years ago


    What kind of questions do they ask?

  • Photo_user_blank_big


    over 7 years ago


    Officer Cooley, I recently scored high on my p.a.t and the next I took my poly,I was as calm as could be and had nothing to hide and sure I would pass this test with no problem,however the examiner tested me 6 times, no break in between and he questioned one of my answers as being false, he asked me to tell him the truth and I would pass the test and move ahead,I told him I had already told him the truth and he then said I had failed and it would be a decision up to my recruiter.My criminal and driving background are perfect,do i still have a chance of being employed, I know they are need of LEO`s.thanks,

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