Thanks. This reminds me of a similar article I read recently, can't remember if I posted it here. These definitions are always evolving, but this particular article I'm thinking of attempted to make some distinctions between psychopath and sociopath. It left me with the impression of DM as a sociopath but not a rage-killing psychopath.
(Before anyone takes issue with these terms, be sure to google. As I said, the definitions and diagnostic criteria change over time.)
I'll try to find it when I'm back at a real computer.
Yes, there ae diagnostic differences between psychopaths and sociopaths. In fact, although the popular concept of a psychopath is of someone violent and criminal, this is not often the case. Most psychopaths stay out of trouble with the law (my source for this is Dr. Robert Hare, the leading authority on psychopathy, who is from B.C. and who developed the diagnostic protocols for identifying psychopaths). The reason most aren't violent offenders is simply they are first and foremost out for Number One, and being incarcerated isn't what they have in mind for themselves. They tend to be callous, narcissistic, exploitative of others, manipulative, parasitic ...and so on.
Psychopaths are identified, clinically, through the use of the PCL-R, the Psychopathy Checklist-Revised, which includes those characteristics listed in the article cited, but how the test is structured and scored is proprietary. It is rather like widely used IQ tests such as the Weschler in that it has a large empirical database from controlled research, requires significant training by professionals licensed to use it, and has high inter-rater reliability (that is, two different test administrations will yield statistically similar scores; this is true of adult IQ tests as well). Besides the characteristics in the list, other items in the subject's background and history are assessed and assigned numerical values. Most people score 5 or lower on the PCL-R; Paul Bernardo scored a 35 - the maximum is 40. To meet criteria for a diagnosis of psychopathy, a person needs a score of 30 or higher.
I'm predicting DM will meet criteria, but if he falls short, I predict it won't be by much. However I'm aware this is armchair speculation. We may never learn what his score is, but it's a virtual certainty he will be assessed after the trial is over, as the results of a psychiatric/psychological evaluation will go into determining his sentencing conditions (not term of sentence).
I may have mentioned it before, but a really good book to read if you're interested in the topic is Dr. Hare's own
Without Conscience: The Disturbing World of the Psychopaths Among Us, which is probably the definitive book for the general reader on the topic. HPL and TPL have it, but you can pick it up easily on Amazon as well. You are almost certain to recognize people you know, as the rate of psychopathy in the general population is up to 5%, meaning most of us have worked with (or for) one, married one, are related to one, or a neighbour to one. IIRC he also provides insightful opinions on how to deal with such people when you meet them.
Here's the Amazon link (reviews etc. are pretty positive)
https://www.amazon.ca/Without-Conscience-Disturbing-World-Psychopaths/dp/1572304510