Saturday, December 31, 2011
Panacea? - Er- No.
The press is getting a bit excited on a slow-news day about the prospect of lie detectors (aka polygraphs) being used in this country. If the reports are correct these gadgets may, under some circumstances, help police to know where to direct their enquiries, and what questions they might usefully ask suspects. As to their usefulness in evidence, forget it. The criminal standard of proof (Beyond Reasonable Doubt) is a very high one, and any half-competent defence brief could make mincemeat of any case that turned on this kind of evidence.