I’m Not Lying – Taking a Police Polygraph is About as Useful as a Screen Door on a Submarine

Okay, so I admit I’ve never been a big fan of lie detectors (polygraphs). Maybe it’s because more than 25 years ago as a young felony prosecutor I was able to easily, and effectively, eviscerate a defense polygraph expert to such a degree that his testimony was virtually unusable in a long-forgotten state kidnapping case. Or maybe it’s because as an experienced criminal defense attorney who does resort to polygraph testing/lie detectors for his own clients in limited pre-charge/early investigation-stage phases, from time to time, I know how easy it is to skew the results by using carefully crafted questions (and also that dry/practice runs are routine to polygraph practice). May be it’s also because as a defense lawyer who has employed innumerable forensic psychiatric defenses in many serious criminal cases, including those involving charges of murder, rape, fraud and embezzlement, I understand that lie detection tests affect different people in so many different ways that it’s virtually impossible for experts to describe a baseline norm, e.g, pathological liars routinely beat polygraphs; inherently nervous people routinely fail. In other words, who’s to say how any one individual will react to such high-stakes scrutiny, and who’s to say whether or not preliminary practice runs are good or bad for any one subject. Or maybe it’s simply because of what I knew as a former state and federal prosecutor (concerning police investigations and data misinterpretation/exaggeration/ mishandling), as well as what I believe as a long-time Massachusetts-based criminal defense attorney; that I am inherently suspicious of any police-administered testing. Whatever the reason, or combination of reasons, I dislike polygraph/lie detection testing to such a degree that I always advise my clients to decline any police/government administered test, and will only consider it in situations that I control, with my own experts, in the privacy of my own law office, where no one ever needs to know the results (if unfavorable) but, me, my client and my expert.

Accordingly, it should come as no surprise that I am not overly excited about recent scientific breakthroughs that suggest brain scans may be able to determine whether or not someone is lying. The current test-case is State of Maryland v. Gary Smith. The Smith case involves allegations that Smith, a veteran Army Ranger, killed his roommate, Michael McQueen, with a handgun. Smith claims that McQueen, also a veteran Ranger, committed suicide. After a procedural history that has seen the case go all the way up to the Maryland Supreme Court following Smith’s initial conviction, Smith has now been remanded for a second trial. This time around, the defendant is seeking to introduce evidence that he’s telling the truth about his roommate’s suicide via brain scans from a Functional Magnetic Resonance Imaging (FMRI) machine that were taken while he was asked questions, including whether he killed McQueen, which supposedly indicate whether or not he is lying. After a battle of the experts, the Judge decided not to allow the admission of the FMRI evidence, basically saying that the use of the technology in this application is so new that it is basically untested and lacks reliability because no baseline standards for using the FMRI have been established for evidentiary purposes of determining witness credibility.

Of course, as someone with two parents who both died of degenerative neurological diseases, I applaud any brain scan advances for living patients and truly hope that better MRI testing will result in better understanding of brain function, as well as related medical breakthroughs in treating brain illness. However, to me, those results are far better utilized in the science lab or hospital ward than in the courtroom, where the results as applied to truthfulness or deception can be extremely misleading, non-trustworthy, and easily manipulated to the introducing party’s benefit.

Currently, in Massachusetts, where my defense practice is primarily based, the law on use/admission of polygraph evidence is that it is inadmissible for any purpose in a criminal trial. Com. v. Martinez, 437 Mass. 84 (2002), citing Com. v. Kent K., 427 Mass. 754, 763 (1998). In Federal Court (District of Massachusetts), where more than ½ of my given criminal case-load is prosecuted, the rules, although similar, are slightly more relaxed. There is no rule that polygraph evidence is per se inadmissible, Conley v. U.S., 332 F.Supp.2d 302 (2004), but polygraph results are rarely admitted in a criminal trial. U.S. v. Rodriguez-Berrios, 573 F.3d 55 (2009), and when they are, usually for a very limited purpose, such as impeachment. And while the results can be introduced in a handful of states (18), the logic behind barring them never changes: they are inherently unreliable; not based on established science; easily manipulated; notoriously errant; and legislators rightfully fear that admission of polygraph evidence, despite all the foregoing caveats, will lead to jurors placing far too much weight on the results.

If they aren’t routinely admissible in Massachusetts, why won’t I allow my clients to take police-administered tests on a "having nothing to lose" proposition? Well, aside from concerns about trick questions, misinterpretation, and outright lying by police experts about results, clients must also understand that while the results may not be admissible, their answers almost always are. If one is prepared to allow his answers to be used against him in court — and believe me, the police will find a way to elicit answers that appear helpful to their theory/prosecution even when a subject is passing "with flying colors" — I suppose I might see a reason one might be willing to submit to one when requested by the police. But that’s never my advice and is always against my professional judgment as I never want to allow the police any opportunity to strengthen their prospective case against my client. Polygraph answers, especially when taken out of context, as they will be, often do just that. So to the question, "The police want me to take a polygraph - what should I do?" My initial advice is to always, "Just say no."

If you have been accused of a crime and you need a lawyer to represent you please contact Brad Bailey at 781-589-2828