Skeptic wrote on Sep 15^th, 2005 at 6:16am:

As an aside, an assumption of guilt and some of the interrogation tactics that are brought to bear as a result is one of the prime reasons false confessions are elicited, with or without the polygraph.  Once an investigator assumes guilt, he or she will proceed to interrogate, rather than interview, and will sometimes use whatever means necessary (hopefully within the law, but that still allows a lot of leeway) to get that confession.  And interestingly, one common way in with false confessions are generated is the presentation of false evidence to the subject that implicates him or her, or otherwise creates a belief in the subject that denial of guilt is useless and that things will actually be better by confessing.  As you might imagine, the confronting of a subject with a polygraph result of "DI" could easily meet this criteria.

Skeptic,

I think you make a good point here. Reminds me of my first experience with the polygraph. The examiner falsely accused me of lying about drug use and selling. After being confronted with a failed test result and then interrogated at length, I was mentally and emotionally exhausted. I felt defeated and had believed so strongly in the poly's accuracy prior to taking one. I remember thinking that if what the examiner is saying is true and I really failed, then no wonder he doesn't believe me --if I were him, I wouldn't believe me, either--not with a failed poly. My belief had been that if someone failed a poly, he or she is guilty of the accusations, period. I was so beat down that for a moment, making things up to please him seemed like it might be the best thing to do just to make it stop. Then, I thought, that's crazy--there's no way I'm going to sit here and make up things that I didn't do--I didn't care about the job, anymore. My examiner told me that if I told him the truth, he would hook me back up to the poly and we could finish the test so that I could pass. I believed the poly worked, so the examiner's promise to hook me back up, kept me from admitting to things that I didn't do. I believed that if I lied about something I didn't do, the machine would show that I was lying. My examiner was successful in convincing me that the purpose of the test was to determine if I measured up to the high moral standards of the FBI and if would lie about anything. I thought the test would reveal my true character and integrity. To me, the test wasn't about drugs (although, even though I knew nothing about the poly, I knew the spying questions were important.)  I thought the test was about honesty and integrity, which kept me from just giving up and giving in, but it was a struggle as the examiner intensely presssured me and tried to trick me many times into admitting to things I didn't do. By the way, I was not interviewed following the in-test. I was interrogated immediately afterwards.  Knowing what I know now, I can't help but feel foolish and wonder how I could have been so stupid and naive to believe that the polygraph could determine lies from truth.