>It is to be noted that around the time Ma applied for employment with the FBI, the Bureau had a roughly 50% polygraph failure rate for special agent applicants, with many honest persons being wrongly branded as liars and barred for life from FBI employment

So either 50% of FBI Applicants were actually foreign agents AND believed in polygraphs (why would they if they were trained foreign agents?) OR it's just total bullshit. I think the "it works if you believe in it and some people do" myth is just that...

It's a very attractive idea that we can tell (even partially) whether someone is lying. We actually might be able to with an fMRI setup I think. But polygraphs should be long gone as rubbish. I have no idea why anyone in the USA takes them seriously.