Forensic Human Factors Analysis for Fatigue Accident Reconstruction
The forensic driver fatigue expert can often conclude to a reasonable degree of scientific certainty whether fatigue was a cause of an accident by doing a human factors accident reconstruction involving two important steps:
- a forensic human factors analysis of the driver’s work-rest history leading up to the accident, and
- a forensic human factors analysis of each particular aspect of the driver’s performance that may have been a cause of the accident.
These steps are discussed in turn below.
Ideally, a commercial driver’s work-rest history will be adequately documented in the “driver’s record of duty status” required by the Federal Motor Carrier Safety Regulations (49 CFR 395.8), and reflect regular work hours and personal routine. Unfortunately, this is not always the case. The driver’s work hours may be very irregular. The driver’s log may be days in arrears, or may be missing altogether. Even if present, the log may be inaccurate or falsified, so it must be tested against other sources. The forensic driver fatigue expert examines many different categories of documents and records using specific tools and techniques, reconstructs the driver’s probable work-rest history, and describes that history in terms of implications for specific factors of driver fatigue.
The human factors expert also studies the particular nature of the driver’s performance that may have been a cause of the accident. This will involve forensic analysis of the driving environment and the driver’s apparent actions in the time period leading up to and including the accident, as related by witnesses, indicated by analyses of physical evidence, and inferred from reconstructions based on engineering and physics. The expert must characterize the driver’s performance with regard to numerous specific human factors elements of driving.
These forensic human factors analyses for fatigue accident reconstruction often permit the forensic driver fatigue expert to identify specific deficiencies of driver performance, to decide whether any of these deficiencies were fatigue related, and to conclude to a reasonable degree of scientific certainty whether fatigue was (or was not) a factor in the accident.