The phrase “a room with no windows” is synonymous with saying “if nobody was watching and there were no punitive consequences.” Doing that which is proper, just and right (musings in a BoA for brethren here) when you have only yourself bearing witness is the highest form of honesty and truth.
This is a question of character and alludes to the discussion of The Moral Compass and tends to touch on how one conducts oneself:
“It is just as cowardly to judge an absent person as it is wicked to strike a defenseless one. Only the ignorant and narrow-minded gossip, for they speak of persons instead of things.” – Lawrence Lovasik
For example: How would you treat/talk about your boss in a room with no windows?