Ash,
If you speak again with this detective, feel free to refer him to this message board. He is welcome to post a defense of CVSA here. His claim that CVSA is 99.9% accurate is unsupported by peer-reviewed scientific research.
The following excerpt from p. 96 of the 1997 CVSA manual provided to trainees by the "National Institute of Truth Verification," which peddles these devices, may interest you (punctuation and spelling errors in the original):
Quote:CREDENTIALS: Tout your experience as a detective or as a CVSA operator. "I have been conducting CVSA exams for ...years". (Brag!) My department selected me to attend the "NATIONAL INSTITUTE FOR TRUTH VERIFICATION"" I have specialized training in sex cases, homicide, child abuse, etc.
CVSA: (Pat or stroke the instrument whenever you mention it.)
(a) This is a foolproof way to begin to FOCUS their attention.
(b) The CVSA is the latest scientific equipment used in law enforcement.
(c) The CVSA is extremely accurate. (If you use percentages less that one hundred the subject may feel that he/she is in the percentage outside of the norm. That is, if you say 97%, he/she may feel they are in the remaining 3%.)
(d) The CVSA is used all over the United States - by local, county, state and federal agencies.
(e) The CVSA is not affected by: drugs, alcohol, age (too young or too old) or the influences normally associated with polygraphs.
(f) The CVSA is housed in a powerful laptop computer with patented software.
But your CVSA examiner might not brag that the "NATIONAL INSTITUTE OF TRUTH VERIFICATION" course for which he was selected was only one week long.
By the way, you'll now find an HTML version of
The Lie Behind the Lie Detector on the AntiPolygraph.org publications page:
http://antipolygraph.org/pubs.shtml While we do not discuss CVSA, you may find the description of polygraph procedure in Chapter 3 to be of interest. Both the CVSA and the polygraph are little more than props for an interrogation, and there are similarities between the tactics employed by operators of both devices.