Quantifying forensic investigations involving bloodstain pattern analysis within the UK

Area of Science:

• Forensic Science
• Criminal Investigations
• Bloodstain Pattern Analysis (BPA)

Background:

• Forensic case data is often confidential, limiting research and academic access to real-world crime details.
• Bridging the gap between forensic practice and academic research is crucial for societal impact.
• This study leverages a unique partnership with a UK police service to access casefile data.

Purpose of the Study:

• To quantify and analyze data from real criminal investigations involving Bloodstain Pattern Analysis (BPA).
• To identify common assault methods, weapons, and bloodstain pattern classifications in criminal cases.
• To provide practice-derived data for researchers and forensic training providers.

Main Methods:

• Examination and quantification of casefiles from 78 criminal investigations between 2012 and 2020.
• Analysis focused on cases involving Bloodstain Pattern Analysis (BPA).
• Identification of assault types, weapons, and bloodstain pattern frequencies.

Main Results:

• Sharp-force trauma was identified as the most prevalent form of assault.
• Impact patterns, despite extensive literature, were classified in only 22% of the examined scenes.
• Quantified data on common assault methods and bloodstain pattern classifications were established.

Conclusions:

• The study provides valuable, practice-based data for forensic researchers and training programs.
• A significant discrepancy exists between the literature on impact patterns and their classification in practice.
• Recommendations include a review and expansion of BPA terminology to encompass commonly observed patterns not currently defined by standards.