Implementing an optimization algorithm to estimate the time of death considering environmental temperature variations

Abstract

During forensic determination of the postmortem interval based on thermometric examination of a body, there may be cases where the ambient temperature at the discovery site has changed over time. In such cases, using the environmental temperature measured at the time of body examination for calculations inevitably leads to errors in estimating the time of death. However, forensic medicine has developed a method that allows calculations under incomplete initial data conditions by optimizing the variables used as predictors in the mathematical model underlying the estimation. This approach is demonstrated through a case study presented in the article.

Using Powell’s optimization algorithm, the study illustrates a formula-based calculation of the postmortem interval when the ambient temperature recorded at the time of examination differs from that during the period the body remained at the discovery site. A computational sheet was developed in Microsoft Excel with numbered cells containing the necessary formulas, making it applicable in forensic medical practice. This approach can be further implemented in the Calc application from the LibreOffice suite or similar software.

In the article presents a practical example of body examination at the discovery site, including rectal thermometry results and postmortem interval calculations without the optimization-based approach for determining individual coefficient values. The case report demonstrates that an expert approach to assessing initial values in a specific investigative context can significantly enhance the accuracy of determining the postmortem interval. This conclusion is supported by the alignment of calculated postmortem interval values with the results obtained through investigative methods.

Keywords

postmortem interval / thermometry / initial modeling conditions / optimization / algorithm / environmental temperature / practical implementation

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