I was flipping around the television channels this afternoon, catching up on daytime pop-culture while consuming my lunch (sometimes a dangerous combination.) In the course of my ‘flipping’ I happened upon the afternoon television show called Swift Justice with Nancy Grace. I am familiar with Nancy Grace and her show on CNN Headline News. She’s a funky-haired, southern-accented, lawyer-with-attitude turned TV show host. I’ve actually watched her Headline News show, mostly in bits and pieces, and I’ve always admired her style and flair. Only today did I discover that she also hosted a syndicated daytime television show which is perhaps best described as a hybrid of The Jerry Springer Show and The People’s Court. To put it as politely as I can, Nancy’s Swift Justice is not my cup of tea.
Having tuned in at the middle of today’s episode, she was in mid-conversation with an “expert” in Layered Voice Analysis. This expert claims that you can use LVA technology to determine when someone is lying or telling the truth. Sound familiar? Did the word polygraph pop into your mind just now? It sure did mine, and at the next commercial break I turned off the show (3 minutes was about all I could take anyway) and looked up some information about this supposed mind-reading technology.
I have blogged before about lie detection devices, specifically polygraphs. Polygraphs are pseudoscientific devices in which their operators claim they can determine if someone is lying. A ‘typical’ polygraph measures and records several physiological responses such as blood pressure, pulse, respiration and skin conductivity while the subject is asked and answers a series of questions, on the theory that false answers will produce distinctive measurements.
LVA, on the other hand, relies on the measurement of ‘brain activity traces’ using the voice as a medium. According to the folks at Nemesysco (the manufacturers of LVA) the traces can be expressed “in terms of stress, excitement, deception, and varying emotional states.” Sounds marvelous, if not extraordinary.
Cutting to the chase, a search of ‘LVA’ plus ‘skeptic’ revealed a 2007 paper authored by Francisco Lacerda of Stockholm University and Anders Erikkson of Gothenburg University, entitled Charlatanry in Forensic Speech Science: A Problem to be Taken Seriously. It was originally published in The International Journal of Speech, Language and the Law (IJSLL).
As Neuroskeptic pointed out in 2009, it reads more like a blog post than a journal paper, and I agree with him that is not necessarily bad thing, so long as the scientific methods employed are sound. In the paper, they analyze the LVA along with a competing product making similar claims as the LVA. Like so many other lie detectors that have come before them, these products turned out to be duds.
From the abstract:
“A lie detector which can reveal lie and deception in some automatic and perfectly reliable way is an old idea we have often met with in science fiction books and comic strips. This is all very well. It is when machines claimed to be lie detectors appear in the context of criminal investigations or security applications that we need to be concerned. In the present paper we will describe two types of ‘deception’ or ‘stress detectors’ (euphemisms to refer to what quite clearly are known as ‘lie detectors’). Both types of detection are claimed to be based on voice analysis but we found no scientific evidence to support the manufacturers’ claims. Indeed, our review of scientific studies will show that these machines perform at chance level when tested for reliability. Given such results and the absence of scientific support for the underlying principles it is justified to view the use of these machines as charlatanry and we argue that there are serious ethical and security reasons to demand that responsible authorities and institutions should not get involved in such practices.”
To make matters worse, Nemesysco demanded that the online version of Lacerda and Erikkson’s paper be withdrawn from the IJSLL. Shamefully, IJSLL caved and did exactly that. Nemesysco’s lawyers then sent letters to Lacerda and Erikkson threatening to sue them for defamation if they published similar articles again.This resulted in criticism of Nemesysco for trying to silence academic research, and of the publisher of the IJSLL for not understanding how to manage a scientific journal.
Make no mistake: attempts by a product’s manufacturer to suppress negative research is a classic strategy employed by purveyors of nonsense, scoundrels, and swindlers.
So the obvious questions should be asked: Does a relatively accomplished, high-profile legal personality such as Nancy Grace have no idea the history of the failure of lie detection technology? More specifically, is she not aware that Nemesysco’s product and behavior are highly suspicious? I sent the following email today to Nancy via her website for the show:
On today’s show, you had an Layered Voice Analysis (LVA) “expert” give the results of the LVA tests he administered. Like all other lie detectors that have come before LVA, there is no compelling scientific evidence that LVA can discern lies. Your utilization of this pseudoscience is much more than a tacit endorsement of lie-detection; it is a disservice to your audience. I suggest you refer to the skeptical literature of these so-called scientific devices, and you will find that under properly controlled testing conditions, lie detectors do not perform as they claim. I would be happy to give you several references upon request.
co-host, The Skeptics’ Guide to the Universe
XM Radio Channel 166
We shall see if Nancy deigns to reply, but I won’t hold my breath. Despite all of this, I still sort of like Nancy’s style and flare. If she could ever come to realize and acknowledge her mistakes, my ‘like’ would turn to ‘love and respect’.