Yes there was a huge mistake on the coroner's part. The blame actually goes further back to the doctors at the hospital also. They should have checked him out for a faint heartbeat. They should have used ice because this will always bring someone back to life in that type of situation.
If the man was declared dead, but he's still alive, then obviously the coroner made a mistake. There's no other rational explanation. What's the alternative -- that he was magically restored to life? No, in this life we have to stick to science and facts. No dead man comes back to life.
The recent event that took place down in Mississippi indeed may be possible on what took place. It is indeed possible that the corner in this small town down in Mississippi in the United States of America could have made a mistake. These mistakes take place time to time across places.
I think he did make a mistake, but since he is no doctor, you can guess where he went wrong.
In pretty much most of the US, coroners don't require medical degrees. The coroner in this case, Dexter Howard, checked the patient's pulse and pronounced him dead. I am not really sure if that is what you're supposed to do because I don't find this the proper technique. So this is where he probably made a mistake.
Howard believed that the man's defibrillator, which was implanted beneath the his skin on his chest, caused his heart to beat again. I am no expert, so I don't know if this is true. Howard had no problem calling this a miracle, and I have to admit; it does seem like a miracle, but that is a different case.
Simply put, yes; he did make a mistake. With that being said, keep in mind that he is no doctor; he does not know how to check to make sure he died.
Holmes County (Miss.) Coroner Dexter Howard pronounced Walter Williams dead at around 9 p.m. The move came after a hospice nurse declared him dead as well and then she called the coroner. An implanted defibrillator, put beneath Williams' skin, supposedly jumpstarted his heart. Still, it's a miracle that the brain didn't suffer a lot of damage from lacking oxygen for at least several minutes. Embalmers were about to start the embalming process when Williams came back to life within the body bag. His resurrection came just in time, apparently.