Body identification is a subfield of forensic science wherein investigators need to identify a body. Forensic (literally, "for the courts") purposes are served by rigorous scientific forensic identification techniques, but these are generally preceded by simply asking bystanders or other persons for the victim's name[1].
If a body is not badly decomposed or damaged, two persons (or one) who knew the deceased well should visually confirm the identity[2].
Authorities will also compare supportive documents such as driver's license, passport, or other authoritative photo ID before accepting a personal identification with which to further their investigative and/or forensic purposes[3].
Of course, any formal investigation should "reality check" additional forensic and scientific evidence to reinforce or question the supposed identity of the victim[4]. Reliable identification becomes increasingly difficult as time passes[5].