All data is evidence. The question becomes is that evidence relevant to the question you are attempting to answer. One uses their experience, education, and training to determine the relevance. The process of elimination is what is used to determine what is relevant. I agree that evidence is needed to formulate a hypothesis. What I have found is that many do not explain in their reports what hypotheses were tested. The reports fail to show where the investigator did seek alternative hypothesis. In most cases, there are more than one hypothesis to be considered.

I disagree that the POE is only a reliable methodology under the SM for certain conditions. Under all conditions, the process of elimination is used from the very beginning when the analysis of the data is being conducted. Maybe you can explain in what condition it cannot be used. Every scientist using the scientific method uses the process of elimination. Why would one think that fire investigation is so special that it differs from other scientific endeavors?

If one does not have all the available evidence should that person be rendering any opinion. All I was saying is that the process of elimination should not have been removed from the document.

I was not suggesting there needs to be a consensus. What I was saying is that when a fire investigator reaches an opinion in most cases it is that person’s opinion only. However, in most cases, the cause being undetermined is presented as if there was insufficient evidence for anyone to reach a different conclusion.

When it comes to the use of the process of elimination the fire investigation profession is no different than any other profession. We, as a profession, need to get out of the idea fire investigators are something special when compared to other professions. I believe the fire investigation profession does use the scientific method. The problem is, just as it is here, is that we cannot agree within our own profession as to the proper application of the scientific method. I will never say a person is ignorant because that person does not agree with my possession. I expect that went multiple persons look and evaluate the same evidence there will be a difference of opinion as to the meaning of that evidence. That does not mean one person is ignorant as compared to the others.

Jim Mazerat
Forensic Investigations Group