What is a limitation of PMI estimation?

Estimating the postmortem interval (PMI) is crucial in forensic science for understanding the timeline of death. One significant limitation of PMI estimation arises if the body has been moved after death. When a corpse is relocated, the conditions that affect decomposition—such as temperature, humidity, and insect activity—can change dramatically. This means that the entomological evidence (the presence and life cycle stage of insects) may no longer correlate accurately with the time of death when compared to the original location where the body was found.

Insects colonize a body based on local environmental conditions, and their life cycles can vary significantly based on the location. If a body is moved, even slight changes in these conditions can mislead estimations, leading to inaccuracies in determining the time of death. Thus, while various factors can influence PMI estimation, the relocation of a body introduces a significant variable that can compromise the reliability of entomological or other biological evidence used for this estimation.