I don't know anything about Matley's credentials, but I did turn up a couple of points on a website yesterday. One, this website included one of his books on a list and gave it a rating of zero stars. Two, the website said that his book was "self-published." To me, that's a real danger signal. Worse than a vanity press.
It has also been pointed out, on other threads, that Matley was the "expert" who testified that the Vince Foster suicide memo was genuine. That is, IMHO, a very sinister connection indeed. It reminds me of that pet pathologist of clinton's, who was always called on to say that some death or other was accidental--including one corpse whose head had been cut off.
Marcel Matley was the "expert" who said that the Vince Foster signature was genuine???? This is the gift that just keeps on giving!!