For example, when a government lies to its people to have an excuse for starting a war, disclosure may save many lives.
What would be a non-idealogical reason? States are driven by ideology as much as you and I are.
Please don't downvote Taphangum for asking a question. If it were chit-chat or a non-contribution style opinion downvote away, but not when it's a quest for knowledge and bettering oneself.