The Polygraph

22 April 2024
Capt. Bob Smith


Many get anxious before taking a polygraph because they don't know what to expect and aren't prepared.  I believe you should have educated yourself before each step in the testing and hiring process to be prepared before your next segment.

Some departments use polygraphs as part of the hiring process.  More than one background investigator will ask candidates if they will submit to a polygraph to verify their information.  You can agree at that time to move along the process but understand they cannot and will not give you a polygraph if it wasn't stated on the job announcement.

If polygraphs are so great, why aren't the results admissible in court cases?  Criminologists say lie detector tests pass 10 percent of the liars and fail 20 percent of the truth-tellers.  If there is a polygraph in your future hiring, check out this website:

There seems to be a pattern of the examiner hammering candidates in one or more areas during a polygraph to try and get them to admit to something that supposedly shows a suspected reaction to a question.  If it is not true, stick to your guns, even if it is questionable. 

I know of candidates who have failed a polygraph, have educated themselves how to get through a polygraph and passed the next.  Others have claimed they purchased programs on the internet and successfully passed the polygraph.

If you don't think there is something going on with the polygraph, consider this:

A candidate contacted me after he showed up for his polygraph.  The evaluator asked him several questions before he hooked him up.  One of the questions he has asked was, had he gone to any websites that offer information how to prepare for a polygraph?  Those sites can't help you anyway, said the evaluator.  The candidate said no (even though he had).

In his background, he had admitted to using pot twice.  One of the questions he was asked when he was hooked was had he smoked pot more than twice.  He answered no.  The evaluator asked him the same question two more times because he said he was getting a reaction.  While preparing for the polygraph, this candidate knew some evaluators use this ploy to get you to change your answer.  There was probably no reaction.  He replied no each time.  Which was the truth.  When the evaluator asked him why he thought there was a reaction each time, the candidate told him he couldn't believe he had to try pot a second time to realize he did not like how he felt when he did.  The interview was over.

Often, candidates get in trouble by what they will say before and after they are wired up for the test.  Understand if you admit to something that you answered no to on your application, you are automatically eliminated from the hiring process.

It's interesting that there seems to be no connection between the information in a psych test and that covered in the polygraph.

I thought the best way to gain more experience for the polygraph is to include information from those that have gone through the process.  The following information has not been verified.  Take what you want and leave the rest.  These postings were gathered from the internet bulletin boards.  Here we go:

Hey bud, I'm not an expert but I have just recently passed my first oral and failed my first background process thanks to the polygraph.  I told some information in my background that probably would have never been found out but being the stupid honest guy thinking I would be praised for testing the truth.  It actually nipped me in the ***.  My background was approved and at the polygraph I again was too honest about something and the ex-sheriff apparently had me depicted as guilty as soon as I explained.  Needless to say, he interrogated me and made me so angry stating that every time I was asked this particular question it was bothering me and stating, are you sure you are telling everything?  I showed a response to this question every time apparently.  I week later I got my letter that my conditional offer of employment had been revoked, but thanks for applying and have a great day!  I know three buddies who passed their polys and are nowhere near being a saint.  Two of them spent $50 on some document they got off of the internet on how to guarantee and pass the polygraph.  I don't know if this would have helped me but if I could do it all over again, I would have taken my buddies' advice and that is tell them what they want to hear and don't offer any info!

More:  I'm currently employed by a fire department in the LA area.  My opinion/advice towards the poly and background check is very simple.  Poly:  There is no way in which a machine could read if you are lying or not.  What this machine does is read your heartbeat, breathing and your sweat glands by attaching two strips of Velcro with cables to 2 fingers.  My opinion about this machine is that the only thing they use this for is to have the examiner drill you on something (drug use, sex life, temper, etc.).  While they are conducting the exam, they pick something to drill you on.  Once they choose something, they drill you constantly until you confess.

Example:  John Doe lied on his application about the one time he smoked pot.  He writes down that he has never used pot.  When he goes to take his poly, the examiner tells him the machine is making a funny reading when he is asked about his drug use (the machine is not actually reading anything funny).  John Doe gets drilled and drilled until John finally confesses.  Because of this, John gets disqualified.  If John would have stuck to his story, he would have never been disqualified.

As for backgrounds, they tell you to be honest.  But sometimes, being honest can bite you in the ***.  When a background is being conducted, the only obvious things they could find out are things like your driving, criminal record and credit history.  Don't be stupid and write down references that hate you.  I've known some good people that should be firefighters/cops but get disqualified for being too honest.

Example:  I know a guy who when he was young was playing basketball one day after school.  After the game, he and a buddy were walking by a classroom, they saw a window open and stole some stuff.  They went home and never got caught.  This dummy was too honest and got disqualified.  There is no way in which anyone would ever find out.

Finally, I am not a background investigator, nor a polygraph examiner.  I do, however, know a lot about this because I have a lot of friends who are cops and firefighters.  While processing to get our jobs, we went through all this.  We share stories and actually talk to these people.  When I was in college, I did a report on the polygraph.  Hey, if OJ Simpson passed his poly, anybody can.  As for your background:  if it's not written down on record anywhere, don't tell them.  They will never find out unless you tell them.

The reason I'm responding to this is because too many good people get disqualified for stupid things.  If you are currently using drugs, they will find out at your medical; if you are weak, you won't pass your PAT; if you are crazy, the psychiatrist will find out.

Still more:  This is the part of the test that worries me too...I have actually taken one before and failed it, though I know that while being tested I was being entirely honest and open about my answers.  The test I took did not want you to have a clean slate so I answered the questions accurately.  After they told me I had failed, they then drilled me to make sure there was not something I did not tell them.  Over and over, are you sure, there must be something in your head you are not letting out.  It was the most frustrating thing to have someone look you in the face and based off a machine tell you you are lying when you are not.

Now, any polygraph I go to I will inevitably be freaked and wonder if I will fail on that fear alone.  I do not have any answers for you, but based on the above, OJ and my story, it seems as though you simply cannot predict just what will happen.

Another one:  I just took my polygraph and passed it.  There was one question that the printout showed the lines going clear off the page, supposedly showing that I was lying.  This proctor drilled me on it.  He almost turned militant and somewhat hostile trying to get me to confess.  The question he asked was, have you ever been fired or asked to resign from a job.  I never have.  I think the best advice I can give from my experience is to stick to your guns and do not let them back you into a corner.  If you know you are telling the truth, this stupid machine isn't going to be able to tell the difference.  The only reason the line went clear off the page was because I took a deep breath.  Not a very dependable reading, if you ask me.

See any patterns here?  Like every step in the hiring process, you don't want to go into a polygraph without being prepared.  Educate yourself!

Thanks to Capt Bob for his insight into this subject!