Post-mortem to ante-mortem facial image comparison for deceased migrant identification

Area of Science:

• Forensic Science
• Anthropology
• Odontology

Background:

• Deceased migrant identification is a global challenge due to various factors including distance, post-mortem conditions, and data limitations.
• Facial image comparison offers a low-tech, fast, and easily transferable solution, particularly when only initial ante-mortem data is available.

Purpose of the Study:

• To propose and evaluate a tailored protocol for post-mortem to ante-mortem facial image comparison in migrant identification scenarios.
• To assess the protocol's usefulness, reproducibility, and accuracy, especially for practitioners with varying experience levels.

Main Methods:

• An inter-observer and accuracy study was conducted using 29 forensic cases with post-mortem and ante-mortem images.
• A four-phase protocol guided practitioners through facial image comparison, from broad to detailed analysis, culminating in exclusion or potential match decisions with a confidence scale.
• Each post-mortem subject was compared against all available ante-mortem targets to simulate a migrant identification scenario.

Main Results:

• The protocol demonstrated usefulness and good reproducibility, with a majority of ante-mortem subjects correctly excluded early on.
• An overall accuracy rate of 85% was achieved, with 79% of non-targets correctly excluded.
• Increased quality and number of ante-mortem images led to more successful matches with higher confidence, and potential matches with non-targets consistently received low support.

Conclusions:

• The developed protocol is a valuable tool for facial image comparison in deceased migrant identification, particularly for less experienced practitioners.
• The study highlighted the protocol's effectiveness in excluding non-targets and identifying potential matches, though minor adjustments were made to mitigate errors.
• The research provides a practical protocol and recording chart to aid practitioners in this critical identification process.