Language speaks louder than actions?

Recent research into police interrogation techniques has produced some interesting results. As this article in the NYT May 15, 2009 reports, researchers who study interrogations and interviews with witnesses and suspects have uncovered behavior details that run counter to "common wisdom":

1. Liars don't look any more shifty or deceitful than honest speakers.
2. Honest people talk more, include more details, and make mistakes,while liars avoid detail and rigidly stick to their story.
3. Asking for information gets far better results than demanding it.

In terms of cognitive accuracy, this makes sense to me. We know that imperatives have little to do with reality, and more to do with wishful thinking and a pre-determined belief in the "truth". By comparison, interrogatives and informatives have more to do with exchanges of information. That police organization have begun to realize that a question tends to produce answers more readily than a demand seems like a good thing.