The idea I am presenting is so easy and obvious you old-timers will probably tell me all about it.

I wonder if the lie detector can detect its own lie?--

Let's say we have a false positive outcome on a CQT.  Of course the examiner doesn't know that, only that the subject failed.  Have polygraphers explored a follow-up test, asking the new relevant question, "did you lie during your examination?"

It seems to me that for a truthful (but failed) subject, this is a less threatening question because it doesn't refer to a crime.  If the second test is failed, that should increse reliability.  It would seem that if the subject is passed on this second question, it would negate the first result and at least stop the damage of a false positive.

If the follow-up test is given before the subject knows he has failed, it would have the greatest reliability because the subject is not under additional stress--my guess.

What do you think?  Has this been done before?

Thanks for taking the time to lead me through this, George.

I can't see anything wrong with asking "did you lie" as a follow-up relevant question to check on the previous test question.  If a person passes the follow-up question, then that flags a previous "deception indicated" as a false positive.

I am thinking about putting my idea to William Iacono at the University of Minnesota to see his reaction.  But, I thought before I look like a fool, I would see if anybody here had heard of this approach before.

A big problem with the CQT is the overly-honest person.  If he tells the truth on the "probable-lie" control questions, then he sets their reference level so low that it condemns him to failing the relevant question.  But, I'm not so sure my "did you lie" question solves the problem.  I am still looking for a better idea.


George W. Maschke wrote on Mar 13^th, 2009 at 5:58pm: