The Polygraph

(Lie Detector)

By Mr. Smartypants


This report is all about thee oh so great and wonderful piece of technology called the polygraph (lie detector). Have you ever wanted to know if someone’s lying?  Have you ever wondered if your brother really did steal your Halloween candy?  If you have, here’s some interesting info on how the top investigators find out.  In this report you can learn more about what it is or does, how it works and last but not least the history.

What it is or does

You probably know what a lie detector does, if you don’t, it detects lies. You may be questioning yourself what the difference is between a lie detector and a polygraph is. If you are, according to Wikipedia there is no difference. Police, other investigators, and victims of theft use it against suspects today.  However, many times the polygraph test fails.  Many important people have passed.  Here are some spies that did -- Ignatz Theodor Griebl, Karel Frantisek Koecher, Jiri Pasovsky, Larry Wu-Tai Chin, Aldrich Hazen Ames, Ana Belen Montes, and Leandro Aragoncillo.  The Polygraph is very unreliable, there even is a whole website against it called

How it works

You may be wondering how a lie detector works, if you have, read this.  According to Kevin Bonsor, the lie detectors put a band around your arm, they put the things that the doctors put on your fingers too get your pulse… they ask you questions… you tell a lie.  You watch the screen in front of them, the pulse rates go up, your skin softness goes up, your smile is unnatural, and they know what you did.


According to Wikipedia, long ago in ancient China and West Africa they had their own system to detect lies.  In China the suspect would have a cup of rice put in their mouth during the prosecutor’s speech, if the rice was still in the suspects mouth at the end of the speech, they would be declared guilty because they thought that since when you lie, your mouth would become guilty because when you lie your mouth is dry.

In 1913 William Moulton Marston, from Harvard University first used blood pressure to detect lies.  Later, a man named Dr. John Larson made it better by detecting sudden physical changes in pulse rate, skin softness, and “other” things.


In conclusion, I hope you don’t ever have to tested by a lie detector, or test someone with one.  I’d like to give a special thanks to Wikipedia, Kevin Bonsor, and you for taking your time to listen to / read this report.