Michael G. Brock, MA, LLP, CSW is licensed as both a master’s level psychologist and a certified social worker. He is in private practice at Counseling and Evaluation Services in Wyandotte, MI. Brock has been in the therapy field since 1974 and, in the past five years, custody evaluations have become the majority of his practice. Brock has done over 200 evaluations.  


By Michael G. Brock

Recently, I was approached by someone whose lawyer had advised him to take a polygraph in a criminal case.  His first trial had resulted in a hung jury.  The prosecution had stated that they would drop the case if the polygraph “proved” the defendant’s innocence.  According to the client, he appeared without counsel to take the exam, and was bullied by the polygraph operator before talking the test.  Subsequently, he was told that he had failed the test, and that things would go easier on him if he gave them a confession.  He complied with the request, virtually assuring a conviction if the case were retried.

Exactly why any attorney would be stupid enough to have his client take a polygraph in a criminal case is beyond me.  First of all, taking a polygraph is an attempt to prove one’s innocence.  Once you start trying to prove the negative you are already in trouble.  

A competent attorney will have his own polygrapher examine his client before sending him to one given by the prosecution/law enforcement officers.  Some people do well on the tests because they are so sociopathic they can lie without anxiety.  Some do poorly because they are anxious and fearful people by nature.  An attorney has to know the psychology of the person he is dealing with.

Even then, the wisdom of taking a polygraph is questionable.  To take one without counsel present is absurd.  Police will often lie to people who have passed the polygraph in an effort to extort a confession, telling them that they failed.  Strange as it may sound, there is nothing illegal about this.  An honest prosecutor or police officer (an oxymoron?) will admit that the main value of the polygraph is to get this confession, since the results are not admissible in court.  Any attorney who doesn’t know this is incompetent.

That brings me to another point.  I have noticed that one of the more difficult things in life is for a defendant in a criminal case to convince his attorney that he has a case.  The notion that everyone who is charge with a crime is guilty is deeply ingrained in those who practice in the criminal justice system, even many defense attorneys.  If I were seeking legal counsel, I would want to be sure before I hired someone that they believed in my innocence.  

Moreover, I would also watch out for the lawyer who makes a good living by taking on a lot of cases and plea bargaining everyone-including the innocent client.  This requires little work, and can be a good deal for the guilty, but innocent need someone who is willing to fight for them.

The following is the text of a letter written to a family court judge who asked my opinion of using the polygraph in child abuse allegation cases.  Note that the American Psychological Association considers the polygraph to be only 61% reliable or, 11% more reliable than a random guess.  If I could not do better than that with the tools of my trade, I would start a janitorial service.  I have found that checking and cross-referencing sources of data while looking for a convergence of evidence is the most reliable way of telling who is telling the truth about what.  The follow is the text of the referenced letter.  The referenced articles are not attached, but are available on the net:

Dear Judge:

I am writing you to follow up our short conversation of last week regarding the use of the polygraph in custody evaluations.  Upon researching the APA literature on the net, I found that ¾ of the psychologists polled did not believe that the test had the 85% validity that the proponents claim for it.  Most estimated its effectiveness at around 61%.  I consulted my colleague, forensic psychologist James Bow PhD, for his opinion on the matter.  Dr. Bow responded that since the polygraph itself is not admissible as evidence in court, the psychologist who includes this information in his report might have invalidated his findings.  

Consider also that the polygraph is not a psychological tool.  I don’t know what the guidelines are for administering the test, but the expert that Attorney P. L. referred me to, Larry Wasser, who is on the Board of Directors for Polygraph Examiners and received that appointment from then Governor Blanchard, told me that he does not yet have a bachelor’s degree.  He may be very good at what he does, but is his function to sway the outcome of a psychological evaluation?

I have included the APA study, two articles of mine, one published and one not as yet published, dealing with true and false allegations of abuse, an article about how to beat the polygraph (which most psychologists believe is possible), and an article on the Specialty Guidelines for Forensic Psychologists. 

Note that these guidelines call for psychologists to give evidence only in areas in which they are trained and which fall within their area of expertise.  Since the 12 points of the Michigan Child Custody Statute are largely psychological in content, a psychologist may appropriately give an opinion about them.  

However, whether or not the polygraph is a sound scientific tool, no one receives training in it as part of a psychological graduate program.  Therefore, the question becomes who is providing the evidence?  The person on the stand may be a PhD or an MA, but the polygrapher may not have any degree.  Shouldn’t he testify about his own findings?  Lawyers who don’t like my recommendations sometimes try to say that I am not qualified (though by Michigan Law I can do anything a PhD can do).  Are they more willing to accept the recommendations of someone with no degree?

Finally, if the accused fails the polygraph, he will be undoubtedly limited in his visitation or visitation will be eliminated all together.  What will happen to the false accuser?  Will that person receive consequences?  My experience is that even when there is plenty of evidence these cases are never prosecuted.  Moreover, is the fact of whether either of them is lying highly significant in any given case?  

You received a report from me this week in which both the Protective Services worker and I concluded that the mother’s allegations of sexual abuse of the child were unfounded.  (I have an extensive file of forensic articles on allegations of abuse if you would ever like to read or copy it).  If the mother failed a lie detector test, would you suggest prosecution?  

In this case, I suggested some additional time with her child, but that the child, the majority of whose parenting time she voluntarily gave to the father, continue to spend the majority of time with her dad.

I am a peacemaker, and am suspicious of the prosecutor and his tools.  I do not want to make a civil case into a criminal case.  I would rather make a civil case more civil.  However, If you have any material that might change my mind, I would be happy to look it over.  Thanks for discussing your ideas with me.

Yours truly,

Michael G. Brock MA, LLP, CSW 

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