Duties always include determining the cause, time, and manner of death. This uses the same investigatory skills of a police detective in most cases, because the answers are available from the circumstances, scene, and recent medical records.
In many American jurisdictions, any death not certified by the person's own physician must be referred to the medical examiner. If an individual dies outside of his or her state of residence, the coroner of the state in which the death took place issues the death certificate.
Only a small percentage of deaths require an autopsy to determine the time, cause and manner of death