In the scenarios you described, what would happen if you did not attempt to classify the fire in your report but only used the facts as outlined in the office fire scenario. I previously mention how I would describe the incident. If asked from the information available at that time what inference would this give to how this fire should be classified, I could then say based on know facts the percentage of confidence for my hypothesis as to the classification trends towards the accidental classification. If later a person confesses and I am asked I can say that the new information is cause for a reconsideration of the hypothesis and that based on these new facts the classification trends towards incendiary.

There was a fire loss a number of years ago where a number of experts all agreed the fire originated at a strip outlet. There was the remains of electrical activity in the remains of the outlet that was consistent with a failure that could produce sufficient heat to ignite near by combustibles. Other than this information there was no specific wording such as accidental used in classifying the fire’s cause. Within a year a person confessed to using paper from the trash can in the room, placing it around the strip outlet and set the fire. Because there was no wording such as accidental used in the reports the fact that a person was confessing was not a problem.