CLPEX Chat Board

http://www.komonews.com/news/national/42874827.html

some quotes from this article:
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Defense lawyers from across the country have derided the tests and call them an example of unfair expert testimony. One of them, North Carolina lawyer David Rudolf, who clashed with Shaibani in another case, laughed about the tests in an interview last year.
"He had women sticking their heads in toilets!" he said. "That's just not science. How do you peer review that? How do you test his conclusions?"
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"It's really a question of, is the testing done properly, is it done according to scientifically accepted standards and is it by someone who is a qualified expert?" he said. "There are people who hold themselves out as experts who aren't experts. That's a major issue."
He added: "The type of test you're describing - whether someone could drown in a toilet or would need help - I'm not sure the type of expert who would be able to testify about that. I don't know what the purported qualifications of the new expert is. The old one was essentially a charlatan."
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This is an example of demanding science in an inappropriate way. There are many sorts of forensic analysis that follows the classic model of a theory of physical reality based on scientific knowledge and a testable threshold of data that produces a valid conclusion. But not every practical inquiry can be neatly wedged into that mode. A prosecution "theory" or a defense "theory" is not a scientific theory. It's simply a proposition, a suggestion of what happened. In this case, there's no definable threshold of data. It's in a subject in which no special knowledge is required to view a demonstration and make judgments. Expert testimony may be helpful. For instance, experts may talk about the likelihood of bruising if great force seems to be required. But the defense is right. It's not science, but it can't be called "junk science" unless it pretends to be science. The prosecution walked into this one by not checking out their expert. But they'll be walking into another bog if they push the new results as scientific. And they don't have to. This will not really be expert testimony. I'm not even sure if they're right to hire an "expert." It's not properly a Daubert matter. It's simply a demonstration. It's not "unfair." It's entirely "fair." It only becomes "unfair" if the State is allowed to argue that the results have the weight of valid scientific conclusion. I would hope the judge prevents that, but I see it a lot.

There are no "scientific standards" to be met. There's no valid scientific conclusion that their new expert can render. All he can do is explain his considerations in setting up the demonstration. He can show, for instance, that his subjects were physically similar to the victim. He can show how he determine the water level likely to have obtained at the time of the incident. He can talk about how his subjects were instructed. He can show a number of different subjects simulating the incident. All those things sound "scientific," but he can't legitimately claim to render a scientific conclusion. He can, to be sure, state an experienced-based best guess, a clinical sort of conclusion, but it has no scientific validity. Courts do regularly admit clinical guesses. And a lot of attorneys don't understand the difference. They're not always being dishonest when they sponsor it.

Consider the famous case of George Joseph Smith, accused of drowning more than one wife in bathtubs around 1900:

Using French's description of Bessie Williams when he found her in the bathtub, Spilsbury (a Home Office consulting pathologist) reasoned that Smith must have seized her by the feet and suddenly pulled them up toward himself, sliding the upper part of the body underwater. The sudden flood of water into her nose and throat might cause shock and sudden loss of consciousness, explaining the absence of injuries and minimal signs of drowning.

Neil (Division Detective Inspector Arthur Neil) hired several experienced female divers of the same size and build as the victims. He tried to push them underwater by force but there would be inevitable signs of struggle. Neil then unexpectedly pulled the feet of one of the divers, and her head glided underwater before she knew what happened. Suddenly Neil saw that the woman was no longer moving. He quickly pulled her out of the tub and it took him and a doctor over half an hour to revive her. When she came to, she related that the only thing she remembered was the rush of water before she lost consciousness. Thus was Spilsbury's theory confirmed.

Not a "scientific" test. Not by a scientist, but by a detective. But a simple practical demonstration sufficiently convincing to get Smith convicted and executed. No scientific conclusion was possible or needed.

Gerald I think a lot of people and especially some of those in the "Forensic Sciences" do confuse science with demonstration or what on a lot of ocassions be referred to as "Reconstruction".

Not everything in the courtroom revolves around science but as you pointed out demonstrations reconstructions are a very valuable part. I will have to admit that sometimes demonstrations can go beyond the bounds of reason. Garrison wrote a nice article several years ago on some that were not within reasonable bounds.

I get amused sometimes when I hear a new "forensic scientist" state 'they cannot do that, it is not scientific'. I use to try to explain----but I do not do that anymore----I figure they have a ways to go and eventually they might find the way themselves.

Demonstrations are not science (generally) nor do they have to be. Thanks for pointing that out.