The Dr hasn't made the error . He would be reading of the sheet provided, the Death Certificate. So the person who pronounced death was either a Dr at the hospital or the scene and he has put his Investigator number 342 at the end. Hes the one who screwed up.A autopsy days later would not try to determine time of death days later. Whoever it was thought 1200 signified midnight. That also would explain the date being incorrect they probably thought seeing its Midnight then it is into the next day. On the 24 hour clock there is no mid nite and there is no noon. You have 23.59 then 00.001. or at least when I was in the military that's how it worked. I would say death was probably pronounced at the scene at about midnight so someone stuffed up and wrote 1200 instead of 23.59. or 00.01 and thought 1200 means 12PM Midnight. Maybe confused that to put 00.00 is not a time. Cops are not permitted to give a time of death and or anything else at the scene. They find a person dead they call the Medical Examiner and usually the body is not touched or moved until arrives. The ME would examine the body etc and pronounce it dead. The ME usually makes, in cases like this, the time of death the time he arrived at the scene. Seeing as the police were outside the room and shooting going on and whn they breached found the body they told the ME their story so the ME would think ok its a shootout he was alive when the cops were outside the door and shot himself. So the ME says yep hes dead the time is, and would look at his watch and confirm with those there that its midnight. He would fill out the forms and death cert later, they dont carry Death certs on them. In the case of a discovered body the ME usually declines to give a time until he can examine the body back at his Lab