I agree with that much. Though, I don't know if I understand how it's that exclusive to a detective. [Sorry, Sherlock.]

But having been exposed to a loss of life as well as the stressors of judgement that will end in death is, um... extremely polarizing. Even if it logically should work for the better of everyone to be cooperative... that doesn't account for suspicion, paranoia, anger, fear...

It's hard for people to work together when the element of the unknown overtakes the determination to overcome circumstance.