Examining Differences in the Rate of Decomposition between Frozen and Not Frozen Human Remains using the Accumulated Decomposition Score

Examining Differences in the Rate of Decomposition between Frozen and Not Frozen Human Remains using the Accumulated Decomposition Score

Conference Room C

Sponsoring Professor: Dr. Daniel J. Wescott

Author Name: Shelby Garza

Author Email: slh254@txstate.edu

Title: Examining Differences in the Rate of Decomposition between Frozen and Not Frozen Human Remains using the Accumulated Decomposition Score

Academic Affiliation: Texas State University

ABSTRACT:

In a forensic setting, it is crucial to know the effect of freezing on decomposition rates. There are cases in where the victim of a homicide is placed in a freezer prior to relocation. A previous study by Roberts and Dabbs¹ using the total body score (TBS) method² found significant differences in the rate of decomposition between previously frozen and never frozen pigs. However, a study on human remains³ using 20 samples (10 frozen, 10 not frozen) placed in an outdoor setting at the Forensic Anthropology Center at Texas State in San Marcos, TX found no significant difference between frozen and never frozen bodies using TBS at 100, 300, and 500 accumulated degree-days (ADD). However, there is currently debate on whether the TBS method can accurately measure the post mortem interval (PMI). For this reason, it is important to test these results using another scoring method. The purpose of this study is to examine the difference in rate of decomposition between previously frozen and never frozen remains using a newly developed gross morphological method known as the accumulated decomposition score (ADS)⁴. Using the same sample, ADS was calculated at 100, 300, and 500 ADD. The results of the ADS method have validated the previously documented results that there is no significant difference in the rate of decomposition between previously frozen and never frozen human remains. Therefore, the rate of decomposition post thawing appears to be consistent for both frozen and unfrozen remains.

KEYWORDS: Forensic Anthropology, Decomposition, Frozen, Total Body Score,

Accumulated Decomposition Score

WORKING REFERENCES:

¹Roberts LG, Dabbs GR. A taphonomic study exploring the differences in decomposition rate and manner between frozen and never frozen domestic pigs. J Forensic Sci 2015;60(3):588-594.

²Megyesi MS, Nawrocki SP, Haskell NH. Using accumulated degree-days to estimate the postmortem interval from decomposed human remains. J Forensic Sci 2005;50(3):618-26.

³Garza S, Wescott DJ. Differences in rate of decomposition between frozen and non-frozen human remains. Proc Am Acad Forensic Sci 2017;23:214 American Academy of Forensic Sciences, New Orleans, LA.

⁴Gleiber DS, Meckel LA, Siegert CC, McDaneld CP, Pyle JA, Wescott DJ. Accumulated decomposition score (ADS): an alternative method to TBS for quantifying gross morphological changes associated with decomposition. Proc Am Acad Forensic Sci 2017;23:206. American Academy of Forensic Sciences, New Orleans, LA.