How to Explain Everything That's in the Room

If you can explain everything that's in the room by staying in the room for an explanation, it's probably not a homicide. If there was a single gunshot wound, and he said that's his gun,. It's registered to him. He keeps it in a safe in the corner of the room. Well now I've got a cause that's outside the room. Now everything shifts to homicide. Why? Because the best explanation for the stuff that’s in the room is a cause inside the room. So what we're doing basically is looking for intruders. Do we have a good reason to believe we have an intruder? This is an intruder investigation. Intruders are what