On December 17, 2015, Steven Sitler’s probation officer wrote a Special Progress Report to the Honorable Judge Stegner regarding her charge. Item #3 states:

“However, Mr. Sitler will be required to submit to a polygraph every three (3) months for his term of supervision and a plesythmograph [sic] upon his son’s third (3) birthday regardless of any future decision that is made involving his living arrangements.”

Since we just remembered the third birthday of Steven Sitler’s child, this brings us to our subject — plethysmography. What is a plethysmograph?

I took the following quote from the National Center for Biotechnology Information’s website. The article is titled “Assessing Sex Offenders”; the subsection is titled “Penile Plethysmography”:

Penile Plethysmography

Currently, the only “objective” means of assessing pedophilic sexual interest is by directly measuring penile erections in response to visual, auditory, or emotional cues. Penile plethysmography, a technique developed over 40 years ago, is used to measure changes in penile arousal in response to such stimulation. The two types of penile plethysmography widely used today measure changes in either penile volume or circumference.

Volume plethysmography measures the displacement of air in a cylinder enclosing the penis — typically, a glass or rigid cylinder is placed over the penis with an inflatable cuff that encloses the base of the penis. When the penis becomes erect and engorged with blood, air is displaced within the cylinder. The resultant increase in the intra-cylinder pressure is then used to calculate an indirect measure of penile volume. Alternatively, circumferential plethysmography directly measures changes in penile diameter in response to sexual stimuli and has been demonstrated as an effective method of measuring sexual arousal. A mercury strain gauge is placed around the base of the penis and is connected to an instrument that monitors small alterations in voltage through the strain gauge. Before applying the strain gauge to a subject, the device is calibrated to correlate changes in voltage with known diameter settings. As a subject is exposed to sexual stimuli, alterations in voltage through the strain gauge are monitored and converted to penile diameter size based upon on the pre-calibrated settings. Both volume and circumferential plethysmography should be administered in a controlled environment that minimizes exposure to external stimuli that might interfere with test results (a dark, sound attenuated booth is ideal).

Studies suggest that volume plethysmography is more sensitive than circumferential plethysmography in measuring small changes in penile erections. However, volume plethysmography is a more technically cumbersome procedure and may be associated with movement artifacts as well as inaccurate measurements due to inadequate cuff seal around the base of the penis. A study by Kuban, et al., in 1999 suggested that volume plethysmography and circumferential plethysmography highly correlated with each other when subjects reached 10 percent of full erection or a 2.5mm increase in penile circumference. Circumferential plethysmography is more commonly used due to its ease of application, lower potential of technical error in applying the device, and equal accuracy of detecting penile erections. However, volume plethysmography may be the test of choice when detecting small changes in penile arousal is necessary (i.e., when using stimuli that may elicit less than a 10-percent erection).

Penile plethysmography test results are often used to characterize patterns of deviant sexual arousal, develop treatment plans, and monitor the effectiveness of treatment. . . . (Assessing Sex Offenders)

A penile plethysmograph is a lie detector for the penis. Steven Sitler will sit in a shaded room on a cozy chair, where the Idaho Department of Correction shall wire his genital to an exceedingly sensitive measuring device. Then Mr. Sitler will listen to stories that include explicit sexual content. Some of the stories will involve children (even children’s voices). The plethysmograph will measure Mr. Sitler’s penile response to what he hears. Then Mr. Sitler will be shown a slide presentation, which will include sexually suggestive images — including images of children (no porn). Again, the plethysmograph will reveal what arouses Mr. Sitler and what does not. The State wants to determine if his sexual orientation has changed.

And please don’t feel sorry for Steven Sitler because he must undergo this humiliating procedure. Mr. Sitler cannot suffer any injury, indignity, or injustice compared to what he inflicted upon his victims.