Bone color changes and interpretation of the temperature/duration of fire exposure to human remains in the forensic context

Abstract

In both the archeological and forensic literature, experimental data have been used to equate the color of burned bone with the temperature to which it was exposed. While this may be applicable in the tightly controlled oxidizing environment of a furnace or crematorium, it is not representative of the more realistic dynamic conditions of fire events involving structures, vehicles, outdoors, and so forth, that are encountered in forensic anthropology casework. In this piece, we review the literature at the cross section of bone color and temperature and compare it to our own observations from experimental burns. We generate a cautionary path forward for future research as well as interpretation in applied contexts. Implying temperature based on burned bone color ignores other significant variables that are related to the degradation of the bone's organic matrix like, the amounts and types of fuels, duration, fluctuations of temperature, oxygen level of the environment, byproducts of combustion, and other variables unique to each scene. Research results on bone color and temperature derived from controlled environments using non‐fleshed bone samples, are not applicable for use in forensic casework involving burned human remains from fleshed bodies. We argue that to do so distracts from other contributing variables and information that can be derived from the analysis of fire patterns on burned human remains and burned bones. Finally, we caution about using bone color alone to estimate temperatures of the fire, which makes incorrect assumptions about fire behavior and could jeopardize court testimony if this method is used as a standard. We raise three issues if a direct correlation between temperature and bone color are used in court: (1) other important factors are ignored, (2) a universal unvaried exposure of the body is assumed, and (3) the expert risks impeachment given conflicting data on the correlation.This article is categorized under: Forensic Medicine > Death Scene Investigation Forensic Anthropology > Taphonomic Changes and the Environment