Sex Offenders, and the Court
Kenneth E. Blackstone
polygraph remains a controversial subject in sex offender treatment. Many writings discuss the advantages and
disadvantages of its use in our work; a patient reader could spend hours on ATSA’s
listserv reading threads and comments that alternately prescribe and condemning
its use in our field. The use of the
polygraph varies from one jurisdiction to the next; and the sensitive nature of
sexually violent predator laws has helped bring the polygraph into the
Kenneth E. Blackstone
the wake of the Arizona decision (Jacobsen v. Superior Court and State of
Arizona), and recent articles (Prescott 2012, Cook 2011), it is important that
we, as treatment providers, researchers and policy advisors, view the polygraph
through an informed and fresh lens. Ken
Blackstone’s latest work provides professionals that opportunity.
Ken Blackstone has conducted
polygraph examinations since 1979.
During this time, he has been involved in more than 23,000 polygraph
examinations as an examiner, consultant, and expert witness and has
independently conducted more than 15,000 examinations. He has also authored
several papers and amicus briefs on related subjects (his web site is www.blackstonepolygraph.com).
In Polygraph, Sex Offenders and the Court, Blackstone explores topics
such as the historical and current state of sexual offender civil commitment.
He follows this with the workings of the modern polygraph, the different types
of polygraph exams, and the best conditions for each. Blackstone takes time to discuss relevant
case law and court rulings regarding the use of the polygraph. For those involved in mandated polygraph
examinations, these discussions and decisions are essential and they should be
well known to us as professionals.
challenges the status quo, arguing for increased quality assurance in the field
and narrowing the scope of the polygraph.
He goes to great lengths to detail the proper use and wording of
relevant questions and contrasts this with the downfalls of improper use,
wording and interpretations. For example, he recommends re-wording an improperly
written question, “did you mean to shoot that man?” as “did you shoot that man
on January 24th, 2004?” Likewise, he replaces “did you penetrate
that 8 year old girl for sexual gratification?” with “did you penetrate your
granddaughter’s vagina on June 3rd?”
challenges polygraph examiners and treatment providers to better differentiate forensic
tests and utility tests. A utility test
is a screening test and “in the psychophysiological detection of deception, as
in any other field, the diagnostic test is always more reliable than the
screening test” (p. 41). His goal is consistency
and increased validity of individual examinations as well as enhanced
professional and ethical standards.
argues that routine practices of “fishing expeditions” and poor wording of
relevant questions decrease the reliability of the polygraph and increase the
likelihood of false positives, resulting in a misuse and misallocation of
financial and supervision resources, wrongful probation violations, and undue
stress on clients.
debate over the position of the polygraph in sex offender treatment and
management will likely continue for years. Polygraph,
Sex Offenders, and the Court conversely offers a foundation of knowledge
and understanding for those of us in the trenches that may, or may not, have a
say in whether polygraphs are utilized in our jurisdictions and practices.
Arizona Supreme Court (Jacobsen
v. Superior Court and State of Arizona, Supreme Ct. No. CV-10-0309-PR
K. (2011). Polygraph, sex offenders, and the court: What professionals
should know about polygraph...and a lot more. Concord, MA: Emerson Books.
Cook, R.D. (2011, Autumn). The
Sexual History Polygraph Examination: Is it time for change? ATSA Forum, 23, 4.
D.S. (2012, Spring). What Do Young People Learn from
Coercion? Polygraph Examinations with Youth Who have Sexually Abused. ATSA Forum, 24.
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