In the Death Note anime episode 30, Near has a call with L2, aka Light and the task force. When he gets the information that a Shimigami is in the room with them, he concludes that Kira must be in the room. Why is it so? Or, if it's logical, why nobody else, especially Light thought about it?
Edit: I just remembered in the morning that he concludes so because the Shimigami is lying. How did Light not think about that, what it will mean to the others, not just Near.