(4 years, 5 months ago)
Public Bill CommitteesQ
Mark Fairhurst: Yes, without a doubt. At the moment, we only have these two programmes: healthy identity and desist and disengage. We need to look at alternatives, because the far right is a completely different dynamic. It has not really raised its head above the parapet in our prisons at this moment in time, but I can assure you that it is on its way, because it is on the rise.
Q
Mark Fairhurst: Yes, I agree with that. It will be an essential tool, but it would also be essential if we had an incentive to release people early, and prior to their release they were given a polygraph and asked about their future intentions. That is something else to consider. I agree: it is very useful. I have no opposition to it.
(4 years, 5 months ago)
Public Bill CommitteesQ
Professor Grubin: It is not valuable at all. You cannot use polygraph testing as a means of testing intentions. The polygraph is looking specifically at behaviours. Your colleague referred to concrete, very narrow questions of the type, “Have you done this?” They can be screening-type questions, or they can be very specific, such as, “Did you rob the bank?”, “Did you shoot the gun?” or whatever. It is not a tool for eliciting intentions or validating responses to those sorts of question.
Q
Professor Grubin: For people with an intellectual disability, you are absolutely right that the accuracy of the test decreases once IQ drops below a certain level. In the sex offender testing, we will typically test down to 60, but we are much more cautious with the test outcome. It is still valuable, because of the disclosure aspect; you still get information and information gain—the point about information gain is the main one I want to leave you with—from the test, even with someone with an intellectual disability.
Again, examiners need to be trained; they need to address their questions in a different way, one that is much more concrete. The test has to be modified. It has to be shorter because of fatigue and issues such as that. So, you are absolutely right that accuracy decreases, but you must remember that nothing hinges on a test outcome alone. If it is a deceptive response and you have no other concerns, you would still look further. You might say, “We have to be more cautious because of IQ.”
There is no evidence to suggest it works any differently with people with personality disorders from how it works with anybody else. Again, because of misunder- standings about how polygraph works, people think, “It does not work with psychopathic individuals because they don’t feel anxiety.” First, the test is not based on anxiety. Sometimes when we do talks, and we will have an examiner, we can do demonstrations of polygraph testing. We used to like to get a volunteer from the audience who we can hook up. I try to pick somebody who is also a psychopath, so we can kill two birds with one stone. I know that here we would not be able to do that, but in the audiences I speak to there are often one or two psychiatrists who would fit the bill for a psychopath. There has been some testing of personality disorders and there is no evidence that the test itself is any less valuable. Again, part of the training of the examiner is that they need to know how to interview these individuals, because of the challenges that they may present.
I believe the third group you were thinking about was those with neurodevelopmental disorder or autistic spectrum disorder. Again, the evidence is that the test works just as well with them as with anybody else, but you have to make allowances in the interview, because of the concrete nature of a lot of their thinking, language difficulties and so on. You need to take that into account in terms of the interviewing, but there is no evidence to suggest that the test itself works any differently with them from how it works with anybody else.