In the case of the 416 fire (I am not familiar with the particulars as I haven’t spent the time reading up on it.) and in my opinion, such a fire should be ruled accidental. You can still assign responsibility for an accidental fire. Arson is intentional, accidents are not.

I am not sure how that works. If the evidence is weak and only circumstantial, then they cannot rule out arson. And if arson cannot be ruled out, the weak evidence of cause is not sufficient, so the cause has to be "undetermined." If the cause is "undetermined," can they then rule it to be "accidental"?

I don't see how one can know that the cause was an accident if they do not know what the actual cause was. If they don't know what the actual cause was, they cannot rule out arson.

If they can't rule out arson, they cannot be sure that the cause was accidental.

I take it that you are speaking specifically on the 416 fire. Correct? It looks as though the government assigns responsibility to the railroad. I have read the entire 416 fire topic thread and based on the information contained there, I believe the government’s findings to be reasonable. I would classify it as an accidental/unintentional fire. They have concluded through their investigation that the cause was the passing train. In the case of that fire, they reached a determination.

I do not see sufficient evidence to accuse someone of arson based on the information provided in these forums regarding the 416 fire. As I said before suspicion alone is not enough. I believe the findings of the investigation to be reasonable in determining the cause and assigning responsibility for the fire.

To answer your question.... If they can’t find a cause, it should be ruled undetermined. Period. That’s my opinion. In this case, The investigation found a cause.

I can speak with some authority to a different field where arson is a problem: Covered bridges.

There are only five POSSIBLE ways for a covered bridge to ignite:
*A lightning strike.
*A wildfire or forest fire, or blaze in an adjacent building, spreading to the bridge. (Most such bridges do not have a building close enough, and there is evidence either way. At least one covered bridge, Phillipi in West Va., was damaged in 1980 by a massive gasoline spill flowing down the road to the bridge and igniting. Similarly, Honey Run in Ca. was destroyed by the Camp Fire: https://www.redding.com/story/news/2018 ... 014163002/ )
*IF the bridge has electrical lines or lighting (rare), an electrical fault/short.
*A vehicle igniting and setting the bridge ablaze, or sparking a fire by dragging chains or the like.
*Deliberate ignition by a human, i.e. arson.

The typical story:
The neighbors or a driver reports a covered bridge ablaze around ten PM. There's no electrical storm in progress; there are no electrical lines to the bridge; there's no forest fire or wildfire. Setting a wooden bridge ablaze by dragging chains or accidentally throwing a cigarette butt is all but impossible; I could offer you ten million dollars to make it happen and my money would be quite safe.
What's the conclusion?
Honestly, you don't need to check for accelerants or other evidence. You end up scoping the area for kids that came home smelling of gasoline.

Now, in the case of the 416 Fire, the railroad and legal defense only has to cause doubt among a jury. And if they're smart, they could probably find proof of people that have threatened such blazes, or held an anti-railroad stance for years in public forums.

There has been plenty of that on the Durango Herald. But my point about arson is that the evidence against D&S is that their trains have started fires in the past, and the 416 fire started near their track. That may be strong enough evidence if arson could be ruled out. But it cannot be ruled out. When arson is considered as a cause, there can be endless motives for it being done. One of those motives is to make it look like D&S started the fire for the very result we now see unfolding.

Then when you consider that the fire started next to the D&S shortly after a train passed, and there being a plausible motive to make it look like a train started a fire, it points to a reason for a fire starting near the D&S track that is entirely different than the possible reason that their train accidentally started it.

As this is a civil case, the prior fires can be introduced as evidence. That being the case, the government may not need to disprove arson. Remember that in a civil case, the requirement is preponderance of evidence, not proof beyond a reasonable doubt.