I think your lie detector is .. useless as for native speakers.  Let's assume you use the LIE DETECTOR on some subjects in Iraq or someone from Iraq applying to become an Arabic translator.
Have you ever stole anything?  OOPS, I think this is a way of life in any impoverished country.
Have you ever been detained by the police.  Whether I wanted or not, You bet.  It is called living in a police state / dictatorship.   
Etc, etc
Those dumb asses have no cultural or geopolitical understanding of realities in other countries.  Let me make it clear for them.  Corruption, cheating or stealing is the way of life and surviving in almost any country in this world. Good luck with recruiting native speakers.. 
Some of those individuals risked theirs and their families's life to come here and while they have very unique skills, you just treat them like pukes.  You better move your fat asses and do some background investigations.   
Yeah!