Lyric discussion by thenogene 

It's about pedophiles and their post-jail rehabilitation process in certain facilities as far as I can tell. A plethysmograph is a device designed to detect erections. If the subject is aroused at the display of suggestive images of children, they are sent back into 'aversion therapy.' Not sure who the Stewart is that Jello is referring to, though.

Relevant Louis Theroux documentary about the whole rehabilitation process. Pretty interesting. youtube.com/watch

'whole rehabilitation process' Not to imply that it actually rehabilitates them...

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