Determining a new method for estimating the PMI of decomposed remains found in temperate Australia

At present, a reliable method for estimating the post-mortem interval (PMI) of decomposed remains in an Australian context using taphonomic changes occurring during decomposition alone is currently unavailable. Decomposition rates of human remains are climate dependent, therefore the current published methods developed internationally may not be useful for determining PMI in Australian environments. The aim of this study was to assess the validity of previously published methods in a temperate Australian climate and develop a method that is more appropriate in an Australian context.
Between 2014 and 2016, pig carcasses, as an analogue for human remains, were left to decompose on a soil surface during the seasons of Summer and Winter (8 pigs per season, 32 in total) in Greater Western Sydney. Soft tissue changes were recorded at regular intervals during each season and scored according to previously published methods. Temperature data was recorded daily using data loggers and an onsite weather station. A new Western Sydney specific model for determining PMI was also developed using all new data collected. This presentation will discuss the validity of using published methods in determining PMI in an Australian environment and how they compare to the accuracy of the newly developed Western Sydney method.