Transparency
Whenever something happens we naturally build stories around the event. We take in the who, what, when, where, why, and how, associated with what we experience. The stories provide the meaning we derive from the event. If we can’t find all the information we end up filling in the blanks. The problem here is that how we fill in the blanks may change the story, and by extension the meaning of the event. The further we are from an actual event the more likely we are to fill in blanks and alter the meaning of things.
If we are close to the action of an event we would be close to all the information. However, say we are effected by an event that has happened far away from us. We will naturally be far away the information - especially smaller details.
Transparency has to do with those who are close to events - particularly events that effect many people - being honest with those further away so that a more complete meaning of the event is derived by everyone.
More importantly, if the more complete meaning is shared and known by more people, fewer people can fill in the blanks with lies.