Might vary by location, UK guidelines:

Obvious examples that may not require the attendance of a medical professional to pronounce death would be a decapitated or badly decomposed body, multiple body disruptive trauma, where a body is severely burnt or has been subjected to prolonged submersion or has been predated by animals (where the body is missing essential parts).

I was an EMT and we were taught you do CPR until pronouncement, except if there's obvious signs of mortality, of which decapitation is one. Livor/rigor mortis. Shoes off. All obvious signs of mortality.

This isn’t Highlander.