Yes, you are incorrect...
It is irrelevant that he took the polygraph test after he was convicted, and the person who asked the questions and who recorded Jeremy's answers was and is an expert in his own right. He is what they call 'an expert witness', who can testify in criminal proceedings of his findings which arose out of the testing of Jeremy Bamber. His findings are admissible, and as a matter of law, must be accepted, unless a different expert who specialises in that field of expertise provides a conflicting interpretation from the same set of questions, answers and recording captured on various equipment. There is nothing to stop someone who is due to stand trial, from taking a polygraph test before the trial begins, and the results being tendered in as part of the defendants case. In much the same way that the results of a breatholiser or a drugs test can be tended and relied upon...
All the expert witness can say is that someone's stress levels did or didn't rise when certain questions were asked. They cannot say -beyond a shadow of doubt- whether or not they were lying. A stress detector is VERY different from an alcohol or drug detector, both of which can be physically detected in the body, making tests reliable. We all react differently to stress factors, ie, I'd tell the absolute truth but, more than likely, fail a stress test because of the pressure I'd feel myself to be under.
