Accident causation is rarely simple and understanding how incidents truly unfold requires far more than reviewing surface‑level facts. To shed light on the science behind accident investigation and the crucial role expert evidence plays in establishing liability, we spoke with Dr Milos Nedved, who brings extensive experience in accident phenomenology and forensic analysis.
In this Q&A, he explains the mechanisms behind accidents, common contributory factors, and why only a rigorous, methodical investigative process can produce findings that stand up in court. His insights provide valuable guidance for legal practitioners working on incident‑related matters and preparing or relying on expert evidence.
From your perspective, what is “accident phenomenology”, and why is it important for legal practitioners to understand when analysing incidents and liability?
Accident phenomenology is the scientific area examining the mechanisms by which accidents take place. It aims at identifying all accident contributory factors and how these contributory factors combine to lead to an accident.
To uncover all that for a specific accident is not a simple, straightforward task, since accidents take place as a result of many errors and omissions, and their combination is affected by varied background factors.
Without establishing all the above, ideally beyond any reasonable doubt (or, at least, on the balance of probabilities), it is impossible to determine the liabilities.
When investigating accidents, what are the most common contributory factors you see, and how do they typically combine to drive causation?
The most common accident contributory factors are the failures in the area of organisational behaviour (management and organisation), and in the area of individual behaviour (skills, experience, health status, anthropometric data).
Several of such failures sometimes follow each other in a time chain pattern, or sometimes there is a simultaneous occurrence of two or more such failures leading to an accident.
How do you approach the complex interaction between people, hazards, and the environment when reconstructing what occurred?
The complex interaction between people, hazards and the environment has been studied for many decades, and as a result of these studies, several tens of accident sequence models have been formulated to aid accident investigators. Some of these models are relatively simple and can also be used by not very experienced investigators, whilst some more complex models would yield the required results only in the hands of well-trained and experienced investigators.
What makes an accident investigation robust and defensible, particularly when the matter is likely to end up in court?
Only a very robust, systematic and detailed accident investigation process can identify all contributory factors setting the scene for an accident, and the mechanism by which these factors combined to cause an accident. No simplified or superficial accident investigation process results could be relied on and could not be defended in the Court of Law.
What are the key risks when expert evidence is relied on too early, too late, or without adequate underlying factual material?
The key risks for expert evidence are the lack of background information and not having in hand all relevant factual materials before commencing the accident investigation (identifying all accident contributory factors) and accident analysis (discovering the mechanism or mechanisms by which contributory factors combined).
Another key risk for expert evidence are untrained or inexperienced accident investigators.
A strong, comprehensive brief to an accident expert witness from the instructing solicitor is a crucial factor affecting the results of the accident investigation and accident analysis.