However, we also have to

However, we also have to consider the work of people like Paul Ekman, that have established a reasonable basis for arguing that our facial muscles and emotions are difficult to control when we are lying.  Therefore, even if there are dozens of subtleties involved, there seems to be a scientific reason to suggest that our ability to deceive (hide our true intentions) can potentially be detected through external means.

Even if this were possible how can it possibly be translated into identifying and distinguishing a pedophile from say a rapist, a philandering spouse, a dodgy CEO or even a politician (!) just from a lying smile? The concept of a 'pedosmile' reeks of quackery and pseudoscience and it always will. 

I also think that the problem of pedophilia is one that needs much more careful, scientific psychological and sociological study and scrutiny which is why these spanish inquisition, witch hunt approaches should be immediately nipped in the bud. 

An obvious problem area to me is the blatant sexualization of children by the media and fashion industry from the adult replica, skimpy clothes that many children are wearing and also by the media which is constantly promoting skinny, adolescent girls as the epitomy of what is a sexy, attractive female in both magazines and in films.

Film stars, models and many of the general population often spend enormous amounts of time and money dieting, dressing, exercising and having plastic surgery to try and look like....sexy teenagers. Is it any wonder that some men are therefore getting confused messages and that a small minority are even turning into pedophiles, who physically act upon this society conditioned, sexual attraction towards these underaged teenagers who are wearing micro miniskirts and skimpy sexy clothing?