While my stance on forensics is not as negative as the parent comment, I don't see how you are drawing such a sharp distinction between the "science" and the "interpretation". They are not separate things.

When a scientist proposes a new test, they include measurement techniques as well as a method of interpretation. If a medical test is used in a way that is frequently prone to misinterpretation, it would be fair to call that entire test useless.

"If a medical test is used in a way that is frequently prone to misinterpretation, it would be fair to call that entire test useless."

And yet there are many examples of this with malpractice, unnecessary deaths, etc. Lyme tests are notorious for false negatives depending on the lab you use. It's also a widely held belief that you want tests done in the middle of the week instead of on a Friday or weekend because some techs just want to get out of there and are more prone to mistakes.

The reason I'm drawing a hard line is because of fact vs opinion. This same line gets drawn in court. They will ask experts if it's a fact or an opinion that they testified about (usually to attack a witness). Autopsies are full of facts, and then there are opinions on what those facts mean. If it's an opinion, it's possible to counter it with another professional opinion.

The only sort of opinion they should be sharing is included, excluded, or undetermined. Hair is not a "match", but it could include or exclude someone and maybe mathematical probabilities.

I disagree. The canonical example here are p-values. Completely valid and accepted interpretation which will forever be abused. In the medical realm, we see the same things with false-positive and false-negative rates causing massive confusion. An even more recent example is COVID vaccine efficacy. I would take the bet that 90% of the general population could not give the accurate definition of what the definition of efficacy is.

Just curious about the downvotes.

1. Was it he said statistics lie sometimes?

2. Or, questioned 90% efficacy of some Covid vaccines?

I think you are getting downvoted because (hopefully) people recognize I didn't question their efficacy. Just that 90% of people know what that means.

If you are using forensics in a trial, the validity of the "interpretation" part is key to it's use. The reliability of these interpretations has been historically hugely overstated.

Given this history it is absolutely reasonable to reject most forensic evidence unless there actual good science supporting the reliability of expert interpretations.

The usual example is DNA evidence. The two most obvious fallacies are actually called The Prosecutor Fallacy and The Defendant Fallacy because it's so easy for either side to mis-sell what the evidence really means.

It's basically impossible for someone who isn't pretty handy with Bayes to work out the significance for themselves.

The average jury member has no chance.

It may very well be the case that a version of fire analysis that is scientifically rigorous can be done, but this would have nothing to do with how it is typically practiced.

Which is what @giantg2 said:

> The science is generally sound (procedures and theory). Usually it's the prosecutors that present the forensics in a way that misrepresents what the results actually mean.

https://news.ycombinator.com/item?id=28265884

That’s not the same claim. The practitioners who come up with the results are not operating in a scientifically sound or rigorous way. One documentary I watched about a wrongful murder conviction (a man was found to have burned down his house to kill his entire family) had a discussion of how the fire investigators would talk about “feeling the beast” and other nonsense. It is very flattering to describe this as in any way “evidence-based.”