Improving the Data Interpretation Process in Forensic Fire Debris Analysis

Forensic fire debris analysis involves the examination of evidence from a fire scene to determine if an ignitable liquid is present.  Part of this process includes the subjective recognition and comparison of patterns in data from questioned samples to patterns in data from known reference materials.  The proposed research aims to improve the reliability of the data interpretation process in forensic fire debris analysis by investigating various factors involved in the pattern recognition and comparison process.  First, a ground truth data set will be created using physical samples designed to closely resemble the complexity of realistic fire debris evidence.  Some of these samples will be modified by adding gasoline or a similar chemical mixture to obtain a set of data that represent various levels of interpretation difficulty, which will be assessed using an objective, quantitative measure of the data’s degree of support for the identification of gasoline.  Then, practicing forensic fire debris analysts will be invited to interpret data from these ground truth samples as part of an online test designed to determine specific factors related to the interpretation process (Study 1).  Next, a survey of practicing forensic fire debris analysts will be conducted to investigate the factors they consider when performing their interpretations (Study 2).  Information from Studies 1 and 2 will be used to develop practical recommendations related to the data interpretation process.  Through these activities, the proposed research will provide insight into factors involved in the fire debris data interpretation process, increase the foundational body of knowledge in fire debris analysis, and guide the improvement of related procedural standards.  All of these outcomes will improve the consistency and reliability of forensic fire debris analysts’ results, which will contribute to the fair and impartial administration of justice for all.