When is a follow-up investigation deemed necessary?

A follow-up investigation is deemed necessary when new evidence emerges or initial findings are inconsistent. This practice is essential in traffic crash investigations because new information can significantly alter the understanding of how an incident occurred. For example, if witness statements or physical evidence from the scene contradict earlier conclusions, it prompts a deeper examination to ensure accurate determination of fault and the events leading up to the crash.

Considering the situation where no evidence is found during the first investigation doesn't automatically indicate that a follow-up is required. There could be cases where the lack of evidence suggests only that the crash was not complex or that all necessary information was gathered initially.

While situations involving multiple fatalities are serious and may warrant further investigation, not every serious incident necessitates a follow-up unless new evidence or inconsistencies surface. Additionally, changes in statements by involved parties do indicate potential issues that may require further inquiry, but the broader and more encompassing reason for initiating a follow-up investigation is the discovery of new evidence or inconsistencies in initial findings, which can help ensure that the investigative process accurately reflects the events that transpired.