Starting today, the field of expertise in Bloodstain Pattern Analysis (BPA) is open for registration applications.
During two and a half years, the NRGD has been working together with the field to develop the BPA Standards. The Board of Court Experts approved these Standards at the end of 2024. Since then, we have begun assessing the assessors. The first assessments have been completed, and with that, the first BPA experts are now registered. We are pleased to inform you that, as of today, the field is officially open.
This field consists of three different phases in which the experts work:
- Initial examination and documentation phase
- Bloodstain classification and investigative reporting phase
- Evaluative reporting phase
NRGD-registered BPA experts have been assessed on and have been found competent in all three phases.
Initial examination and documentation phase
During this phase, the expert documents where bloodstains are located. The expert also uses presumptive tests to determine if the stains are likely blood. This phase focuses on factually reporting the observations.
Bloodstain classification and investigative reporting phase
In this phase of the investigation, the expert performs the classic BPA tasks. These tasks are: • Classifying and identifying bloodstain patterns
- Determining the locations, orientations, and movements of blood sources
- Determining the sequence of events
- Determining the minimum number of impacts
During this phase, the expert may offer a possible explanation of how the bloodstains were formed, within the context of scenario formation.
Evaluative reporting phase
During this phase, the expert investigates further what happened. The expert compares multiple scenarios and/or hypotheses and evaluates to which of these scenarios or hypotheses the patterns fit best and to what degree. For this, the expert can use Bayesian statistics, assign probabilities to findings, and provide a likelihood ratio in numerical and/or verbal terms.
More information about these three phases and the requirements and limits of the field of expertise of Bloodstain Pattern Analysis can be found in the Standards. If you have questions about the Assessment Framework and how it was developed, you can always contact the NRGD at beheer@nrgd.nl.