Based on the fact that Dr. Glass is a professional I would be willing to bet she is right on the money with the body language. Her interpretations are just that, interpretations at what we all see as a fact, which would be KC's body language. Spoken words are only part of what we take in when we make contact with people. The majority is body language and what we know and what we feel is going on with the person. I would say for the most part LE officers are usually pretty good at body language. We all learn it subconsciously, it's just that some of us are better at interpretations than others. In Dr. Glass' case, she is a well known professional in that field. JMO
I agree about LE officers, I think most of them (experienced LE) are probably very perceptive and observant about body language.
Yes, there is lots of research in communication (including nonverbal communication) which
is scientific, don't get me wrong. (My background is in language and my mom was a teacher of the deaf, and I have had personal experience with people who have brain injuries affecting communication, I'm reasonably aware regarding language/communication, etc. However, offering an assessment of a person one has seen on TV, a person the professional has never even met much less evaluated in any professional capacity, and a person one has heard a lot of spin about, I don't consider that all that scientific. It's one thing for us to just discuss our personal interpretations of the defendant's body language (which I do find interesting, too), but it's something else to state interpretations as fact, much less for a professional to do so in the national media....
There are lots of "experts" out there who like to pretend there are actual specific "meanings" to various gestures, etc, which they will rattle off. I don't consider that very scientific. Nonverbal communication is highly dependent on culture, context, and varies among individuals and in the end, people will vary in how they interpret another person's body language, there is culture, context, personal experience, etc on the receiving end as well.
As you say, we all do interpret body language
all the time. It's such a big part of communication that some people who have cognitive disorders where they can't pick up on nonverbal cues can be very disabled by it.
I'm middle aged so I'm pretty familiar by now with most of the "meanings" popularly assigned to various gestures, etc. (It was very popular back in the '70s, or at least I remember hearing and reading about it back then as a child and being enthralled with it.) Personally I do agree with many things that Dr. Glass said in general. For example, the raised register of a voice, cracking voice, raising of the eybrows, etc, those are usually considered to be hallmarks of deception-- and I have seen cases where I thought exactly the same thing about these.
MOO