Lafayette LX4000 Electrodermal Channel Defect

[George W. Maschke]

On Monday, 20 May 2013, McClatchy Newspapers reported on a defect affecting the electrodermal channel of the Lafayette Instrument Company's LX4000 polygraph system:

http://www.mcclatchydc.com/2013/05/20/191542/glitch-in-widely-used-polygraph.html

The percentage of examinations affected is unknown, but in some cases it's large enough a factor that it can flip outcomes depending on whether the electrodermal channel is scored with data from the instrument's "manual" or "automatic" modes.

I'd be especially interested in the thoughts of polygraph examiners on this matter, especially those who use or have used the LX4000.

Questions that I think are worth addressing include:

1) Should the Quality Control section of polygraph units review all charts produced with the LX4000 for possible discrepancies between outcomes based on whether the manual or automatic EDR EDA mode is used? Why or why not?

2) Since very large numbers of polygraph charts evidently stand in need of review, is this a task that could be automated with software?

3) If you think this is much ado about nothing, and no action is actually warranted, why do you believe that to be true?

And of course, any other points that you think are applicable here would be welcome.

By the way, Criminal Justice Policy Foundation president Eric E. Sterling has what I think is a cogent commentary on this matter here:

http://justiceanddrugs.blogspot.com/2013/05/is-justice-system-blase-about-injustice.html

[Doug Williams]

I was instrumental in getting the polygraph outlawed in the private sector - with the passage of the EMPLOYEE POLYGRAPH PROTECTION ACT, pre-employment polygraph testing became a federal crime!  So what explains this schizophrenia in the government?  They outlaw the polygraph in one area and expand it in another!  I'm afraid I know - I think President Nixon told us why the government uses it when he said, "I don't know anything about polygraphs, and I don't know how accurate they are, but I know they'll scare the hell out of people, and that's why I like to use them!"  I have proved the polygraph is not a "lie detector", so there is no justification for the government to continue to use it on the pretext that it protects our national security - and when you factor in all the damage done to people who are falsely branded as liars by these con men and their unconscionable conduct, the fraud perpetrated by the polygraph industry should be a federal crime in every instance!  Everyone deserves to be protected from this insidious Orwellian instrument of torture!  Shame on anyone who administers these "tests" - and shame on the government for allowing this state sponsored sadism!

[George W. Maschke]

Doug,

I share your dim view of polygraphy, even absent glitches in the equipment. But my purpose in raising the above questions is not to taunt or goad polygraphers, but to encourage cool, rational discussion of a timely topic that is highly relevant to polygraph policy. I think that these questions should be of interest to both proponents and opponents of polygraphy.

Does your computerized polygraph instrument (Axciton, I think?) have both "manual" and "automatic" settings for the electrodermal channel? If so, have you ever noticed different outcomes depending on which setting was used for scoring purposes?

[Doug Williams]

Yes & yes.  And even the old analog instruments have a knob that you can turn to adjust the "sensitivity" of the GSR. 

[George W. Maschke]

The Lafayette Instrument Company denies in a letter to customers also published on its website that any problem exists, averring "There is nothing wrong with the LX4000":

https://www.lafayettepolygraph.com/email/eda-response/

RESPONSE TO RECENT ARTICLES PUBLISHED ONLINE
MAY 22, 2013

Dear Colleagues,

More than two months ago, Lafayette Instrument Company received questions from a journalist regarding our EDA (electrodermal activity sensor), our LX4000 polygraph system, and our business practices. We were not obligated to respond to the questions, but we did respond hoping that we could improve the quality and integrity of the subsequent article. In that regard, we were unsuccessful. On or around May 20, 2013, a series of articles were published online and we feel these articles selectively ignored extensive amounts of data that we provided to the lead journalist.

The complete set of questions, and our responses, can be found here:

http://www.lafayettepolygraph.com/eda-questions.pdf

Additionally, we provided a shorter EDA document to our customers and partners in March (2013):

http://www.lafayettepolygraph.com/eda-info.asp

To summarize:

There is nothing wrong with the LX4000. Implications in the news media regarding LX4000 problems are based in misinformation. We are continuously engaged in research and development to improve all of our products and we are certain that the LX4000 and LX5000 devices represent the best technology available to the profession. The EDA phenomena referenced in the article involves the potential for occasional tracing variations between Manual and Auto EDA; this is a known phenomenon that is documented in psychophysiology literature, and is not unique to devices from Lafayette Instrument. It was irresponsible and misleading to alarm people by labeling a known phenomenon, a "glitch" It was similarly confusing to misuse the term "skew" in an unscientific way. All EDA modes have their advantages and disadvantages. LIC has taken the approach of helping customers evaluate these advantages and select the EDA mode that best meets their needs.

We stand by our products and we will work with you to quickly resolve issues or address further questions as needed.

For more information, or to get to know us better, please contact

Terry Echard
President and General Manager
terry@lafayetteinstrument.com
     

Chris Fausett
Vice President and
Polygraph Product Manager
chris@lafayetteinstrument.com
     

Jennifer Rider
Vice President and CIO
jennifer@lafayetteinstrument.com


Lafayette Instrument Company, Inc.   PO Box 5729 Lafayette, IN 47903   Tel: (765) 423-1505   info@lafayetteinstrument.com

[Doug Williams]

In other words, everyone in the polygraph "profession" knows that referring to the polygraph as a "lie detector" is just BULLSHIT!  So who cares whether the GSR goes a little whacky at times?  After all, the polygraph is just a prop we use to scare the hell out of people anyway.  And, as to "scoring" the test, that too is BULLSHIT!  We all know the "score" of truth or deception is whatever we say it is - we don't have to prove a damn thing to anyone and we don't answer to anyone!

The Lafayette Instrument Company denies in a letter to customers also published on its website that any problem exists, averring "There is nothing wrong with the LX4000":

https://www.lafayettepolygraph.com/email/eda-response/

RESPONSE TO RECENT ARTICLES PUBLISHED ONLINE
MAY 22, 2013

Dear Colleagues,

More than two months ago, Lafayette Instrument Company received questions from a journalist regarding our EDA (electrodermal activity sensor), our LX4000 polygraph system, and our business practices. We were not obligated to respond to the questions, but we did respond hoping that we could improve the quality and integrity of the subsequent article. In that regard, we were unsuccessful. On or around May 20, 2013, a series of articles were published online and we feel these articles selectively ignored extensive amounts of data that we provided to the lead journalist.

The complete set of questions, and our responses, can be found here:

http://www.lafayettepolygraph.com/eda-questions.pdf

Additionally, we provided a shorter EDA document to our customers and partners in March (2013):

http://www.lafayettepolygraph.com/eda-info.asp

To summarize:

There is nothing wrong with the LX4000. Implications in the news media regarding LX4000 problems are based in misinformation. We are continuously engaged in research and development to improve all of our products and we are certain that the LX4000 and LX5000 devices represent the best technology available to the profession. The EDA phenomena referenced in the article involves the potential for occasional tracing variations between Manual and Auto EDA; this is a known phenomenon that is documented in psychophysiology literature, and is not unique to devices from Lafayette Instrument. It was irresponsible and misleading to alarm people by labeling a known phenomenon, a "glitch" It was similarly confusing to misuse the term "skew" in an unscientific way. All EDA modes have their advantages and disadvantages. LIC has taken the approach of helping customers evaluate these advantages and select the EDA mode that best meets their needs.

We stand by our products and we will work with you to quickly resolve issues or address further questions as needed.

For more information, or to get to know us better, please contact

Terry Echard
President and General Manager
terry@lafayetteinstrument.com
     

Chris Fausett
Vice President and
Polygraph Product Manager
chris@lafayetteinstrument.com
     

Jennifer Rider
Vice President and CIO
jennifer@lafayetteinstrument.com


Lafayette Instrument Company, Inc.   PO Box 5729 Lafayette, IN 47903   Tel: (765) 423-1505   info@lafayetteinstrument.com