How can polygraphers tell the difference in results from control vs irrelevant questions???

[Moe]

So I understand that certain countermeasures should be used on control questions and not the irrelevant questions that that the FBI, CIA, and NSA often use in their polygraph.  If a polygraph victim...excuse me...a person being polygraphed for employment, if that person were to use breathing countermeasures on the irrelevant questions, how would this look different on the charts from if those countermeasures were used on the control questions?  What about the polygraph machine charts lets polygrapher distinguish between when countermeasures are being used on one set of questions (like irrelevant questions) from another (like control questions)?  Can the polygraphers magically tell when countermeasures are being used at one time but not another?

On top of that, if government agencies like FBI, CIA, NSA don't use control questions at all, then what countermeasures should be used?

[George W. Maschke]

First, let's clear up some misunderstandings. The FBI, CIA, and NSA's polygraph screening techniques don't "often" use irrelevant questions. They always do.

But the FBI uses a probable-lie control question test (the federal Law Enforcement Pre-Employment Test or LEPET) whereas the CIA and NSA use the relevant/irrelevant technique.

Regardless of the technique used, polygraphers do not expect to see strong or consistent reactions to the irrelevant questions. If they do, countermeasures (from a not-very-clever examinee) may be inferred. Sometimes, the polygrapher may intentionally characterize the irrelevant questions as "control" questions when reviewing them with the examinee during the pre-test phase in an effort to misdirect those who may be contemplating the use of countermeasures.

The most important countermeasures to the relevant/irrelevant technique are probably behavioral (see Chapter 4 of The Lie Behind the Lie Detector). Note that it's quite common for CIA and NSA applicants to initially be accused of holding back information, to be grilled for admissions, and to be brought back for one or two follow-up sessions.

In the relevant/irrelevant technique, polygraphers look for consistent, specific, and significant reactions to any of the relevant questions across multiple chart collections. A strategy for preventing reactions to any one relevant question from standing out is discussed in Chapter 4 of The Lie Behind the Lie Detector (at p. 151 of the 4th edition).

[Moe]

A strategy for preventing reactions to any one relevant question from standing out is discussed in Chapter 4 of The Lie Behind the Lie Detector (at p. 151 of the 4th edition).

Thank you George!  I see that regarding the relevant/irrelevant test on page 151 of that book it says "In addition, recall that with this technique polygraphers look for "consistent, specific, and significant" responses to a particular relevant question over multiple charts. You can prevent such a pattern from occurring by simply producing responses to two differing groups of two relevant questions within the different chart presentations."

Does this mean I should try to produce a reaction, such as thinking scary or exciting thoughts, on two different relevant questions during one set, and then a different two relevant questions on the next set.  By "set", I mean the set of questions asked when being polygraphed when the machine is on.  You usually have multiple "sets" of questions during a polygraph session, where the machine is turned on for a set of questions then when that set ends the polygrapher fiddles with his computer and does whatever with your charts for a few minutes before the next set of questions.

[George W. Maschke]

I think you've grasped the concept.