Before people get too carried away, the reason why he's in trouble isn't that he was teaching people to beat the lie detector. This bit is very important: It's

Before people get too carried away, the reason why he's in trouble isn't that he was teaching people to beat the lie detector. This bit is very important: It's because he was teaching it with knowledge that the techniques would be used for nefarious and illegal things. This is arguably aiding criminal intent. IANAL, but that itself carries a very different connotation with his actions. If he was objectively teaching this to highlight the failures of the detector and showing that it can be beaten, but not directly aiding any criminal activity, it would have been different. The moment he knew the "clients" were engaging in or about to engage in something illegal or legally dubious, he should have distanced himself. And for proof, the article itself mentions that many others who do the same thing, highlight the inadequacies and teach ways to circumvent it, have thus far not been prosecuted.