Wise selection of people. My conversations with "witnesses" and abductees were always on the level. Abductees usually feel quite violated and witnesses of unusual craft tell the same story time after time. They always prohibit you from reading more into their story than they tell. They are sincere.
We were very careful not to ask leading questions but rather totally open questions.
Open questions were like this:
“What did you see?
What happened next?
How did you feel?
That is a great way to get unfiltered information.