Hey there,
The empirical evidence is my own screw ups assuming a certain behaviour out of a passport, which is also consistent with what CRM courses teach. It is true that one can link a passport with a certain body language or a way of approaching issues, but I think I have been proven wrong more times than right. Do I have any CRM material to pass? No, sorry. But in short - and talking by memory - the message is that wrong behaviours in the cockpit are self-fulfilled prophecies, meaning that if you treat another crew member like someone who is not trustworthy, right out of the gate, that crew member will feel like one, and stop taking an interest on what he is doing, performing below his potential and therefore giving the impression of not being trustworthy. Same goes for being on a defensive state of mind, if one perceives the other guy as the arrogant type. It is very easy to antagonize someone that is just showing up to do a job, in the best state of mind possible.
My own experience has shown me that A) everyone knows how to do their job until proven otherwise, and B) everybody else wants the exact same thing as I do: have a good one, go back home, and collect the cash at the end of the month. Once I realized that, I started seeing passport and cultural backgrounds for what they really are, "different non-verbal languages" that most of the time express the same thing. It is on one self to observe to learn those languages.