Maybe the ME’s Office in Knoxville, TN, isn’t the worst in the world.

I was preparing a blog post about the decades’ long problems with medical examiners in Knoxville, TN, when an article on a CNN blog caught my eye: “Canadian Floating Feet Mystery Deepens.” I urge you to read it, if you have any reasonable doubt that juries ought to listen to medical examiners’ courtroom testimony with a great deal of skepticism. (Think Dr. G’s claim that Caylee’s remains proved the manner of death was homicide.)

If you don’t care to read such a gruesome article, here is the punch line:

“For the 11th time in the past four years, a human foot in a sport shoe was found on a Pacific Northwest shoreline. . . . ‘These human remains did not show any evidence of trauma whatsoever,’ CBC quoted [Medical Examiner Stephen] Fonseca as saying.”

Okay, doc, exactly how did the foot become detached from the ankle if it was not by trauma?

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Hot Air and Forensic Science

Some time ago in response to my statement that (like one of the jurors who spoke to the press) I suspected Casey Anthony might have used chloroform as a babysitter, blogger “Voice of Sanity” contacted me:

‘Easy’ to concoct is arguable – it is ‘easy’ to accidentally produce phosgene, a deadly gas, instead. DuPont had a release from their plant, killing a worker. VOS

Two chemistry professors in this video clip from In Session disagree: they claim that not only is it easy to concoct, chloroform is also released from chlorinated swimming-pool water and lingers for a very long time in enclosed spaces, such as a car trunk and a sealed can (used by Orlando CSI’s to capture the gases in the air of the trunk and later tested at Oak Ridge National Labs and the FBI lab). (They also admit that pure chloroform is hard to make, but for most people’s purposes the purity is irrelevant.)

Two pieces of evidence presented at trial hinted that Casey Anthony might have used chloroform to sedate her daughter:

  • a computer search for “how to make chloroform” found on the Anthony-family computer
  • a minute amount of chloroform detected in the air in the car trunk

Unfortunately for the prosecution, the evidence did nothing more than hint; the defense thoroughly shredded the forensic analysis of both the computer search and the air in the trunk—and the jury understood this.

Now that I’ve had time to think about it, the chloroform junk should never have been admitted into evidence. It was nothing but hot air. I am absolutely certain now that chloroform played no role in Caylee Anthony’s death, but not because of the difficulty or ease of concocting it at home.

The idea that chloroform might have been used as a murder weapon came initially from a poorly conducted computer forensics analysis of the Anthony hard drive. First, a police officer created a report listing all the Google searches on the hard drive. He found nothing sinister other than a single search on “how to make chloroform.” Because he did not know how to use the analysis software properly, he put the report he had generated aside for almost a year before asking a real software expert to look at, but he did initiate an investigation into the presence of chloroform in the remains and the “crime scene” (the wooded area and the car). The remains and the wooded area produced no hint of chloroform.

Some time later, forensic anthropologist Voss from Oak Ridge examined the air in the trunk in hopes of discovering it contained gases that would prove a human body had decomposed there, one byproduct of which is chloroform. He ran a test on the air using a gas chronometer/mass spectrometer: an instrument that determines the chemical makeup of a substance. Voss found chloroform in the sample—as expected, since he had been told that a body had decomposed in the trunk.

But he did not conduct a test to determine how much chloroform or any other single chemical was in the sample. Instead, all he did was determine that chloroform was present and was the dominant gas in the sample.

And here is where logic flew out the window: Voss assumed the air was filled with the gases of human decomposition, but his studies of the gases of human composition had never before shown that chloroform was the dominant gas. Therefore, he concluded, most of the chloroform in the car trunk sample must have come from some other source than the victim’s body.

Since he was also told that chloroform intoxication was suspected as the cause of death (because of the Google search), he ran to the prosecution with his GSMS readouts—and a theory of the crime was formed.

Let’s look at the prosecution’s syllogism again:

  1. The gas in the car trunk was from the decomposing body of a child killed with chloroform (a faulty premise).
  2. The gas in the car trunk was composed of too much chloroform to have come entirely from the process of decomposition (if you believe Voss’s database).
  3. Ergo: chloroform was the murder weapon.

What?

There was nothing fishy about the Google search for “how to make chloroform,” because it was made in the context of someone’s visit to the Facebook page of one of Casey Anthony’s boyfriends who had written a remark about winning girls over with chloroform.

There was nothing fishy about the findings of a very, very minute amount of chloroform in the air of a smelly car trunk. Chloroform is present in many common household products and produced by the decomposition of mammal flesh, such as pork chops. It’s even present in pool water in which the child could have drowned, as the defense claimed.

Casey Anthony’s bizarre behavior after her child’s death compels me to believe she felt guilty about something. Her mother’s apparently false testimony about being the one who searched for “how to make chloroform” makes me wonder if she doesn’t suspect Casey used chloroform as a babysitter.

But there is no evidence at all—not a shred—that chloroform had anything to do with Caylee Anthony’s death.

So, I still feel Casey Anthony felt responsible for her daughter’s death—even if it was because she didn’t keep an eye on Caylee when she most needed to, and Caylee sneaked out of the house one June morning to go swimming alone.

The Casey Anthony trial should be a wake-up call to the forensic science community: a few more public spectacles like it will sour the public on the whole profession. “Forensics” may produce intriguing clues the likes of which Sherlock Holmes would delight in, but clues aren’t evidence. Detectives need to get back to basics. Prosecutors need to learn to respect juries and present them with solid cases.

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Casey Anthony’s Brain—Is It a Dangerous Mind?

The dream of criminologists is to find a physical characteristic or set of characteristics that can predict with certainty which children will grow up to be sociopaths. In particular, the issue is what causes “bad seeds," that is, individuals who are predestined to commit crimes, especially murder.

Psychologists have long studied people who lack emotional responses to other human beings, the sort of people that tend to be criminals. In high-profile televised trials, mental-health and FBI profiter commentators typically identify these people as displaying “a flat affect” when confronted with proof of human suffering. You may recall, for example, psychologists describing Scott Peterson’s flat affect (expressionless face) when confronted with photos of his wife’s torso. (Since the Peterson trial was not televised, we have only these commentators’ word for how the defendant looked.)

For over a century, biologists have attempted to find specific defects in the human brain that lead to anti-social behavior. Neurologists in particular have wanted to determine whether genetic defects can be identified in young children.

Why would anyone want to predict criminality in a child? Dr. Adrian Raine of the University of Pennsylvania says, “[I]f I could tell you, as a parent, that your child has a 75-percent chance of becoming a criminal, wouldn’t you want to know and maybe have the chance to do something about it?”

Dr. Raines does not offer any advice for parents of such children, however.

Recently The Chronicle of Higher Education reported that Dr. Raine has proposed that he has found two or three physiological brain defects that are early-childhood indicators of “dangerous minds.” According to Dr. Raine’s theory, sociopaths can be spotted in infancy and sometimes even in the womb.

Studies of the heads of criminals date back to the 1800s. Phrenologists mapped the bumps on human skulls and claimed to be able to determine personality traits of individuals based on their unique bump patterns.

Anthropologists compared human skulls and purported to be able to identify racial differences in bones and particularly in skulls. Paul Broca developed craniometry and believed he could predict personality based on the size and shape of a skull. In addition, this field of anthropology proposed some racist theories about intelligence, too.

During the 20th century, numerous studies were conducted of possible biological causes of aberrant human behavior. In the 1990s, neuroscientist Dr. Antonio Damasio demonstrated that the size of the amygdala (a part of the brain responsible for many emotions) is a predictor of certain behaviors in humans.

In 1997 Dr. Raine applied both Damasio’s theory and another of his own observations involving damage to the prefrontal cortex of the human brain: Raine PET-scanned the heads of 41 convicted murderers with those of 41 “normal” people. Dr. Raine looked at the number of convicted criminals from “good homes” who also had brain abnormalities. He concluded that genetic and biological factors were more influential on criminal minds than were “nurture” factors. In other words, the criminals he studied were born bad. (I have no idea how he defined a “good home.”)

Earlier in his research career, according to The Chronicle of Higher Education, Dr. Raine studied the possibility of predicting specific acts of violence by criminals. He taped electrodes to a number of convicts heads and then locked himself in the back of a van with them. At that point—with prison guards stationed outside to rescue him if necessary—Raine proceeded to do his best to irritate the prisoners in hopes they would snap and try to beat him up. He believed he could predict the moment they snapped using their brainwaves. The experiment was a failure: nothing he did got a rise out of any of them.

In addition, Dr. Raine has found what he refers to as a “hole” known formally as a cavum septum pellucidum. He has found this hole in fetal scans as well as scans of adult criminal brains.

To What End?

First, I would like to point out that Adrian Raine is a private-sector researcher. He conducts his research under the auspices of universities (and in this context even state-owned universities are not public-sector). In addition, while Raine’s research is potentially applicable to forensics, it is not intended to produce evidence of criminality that can be presented in court. His aim is to help caregivers (parents, teachers, mental health professionals) identify potentially problem children in order to provide therapy before they develop sociopathy.

However, it is inevitable that his studies (and similar ones) will be used for highly dubious social engineering purposes. The only acceptable use for this research IMHO is in gene therapy to prevent the development of fetal brains that exhibit these abnormalities.

Casey Anthony’s Mind

I suspect that if the State of Florida could produce brain-scan evidence of Casey Anthony that demonstrated she had a small amygdala, a large frontal cortex, and a hole between the  halves of her brain, they would. Both Ms. Drane-Burdick and Mr. Ashton appear to me to have a visceral dislike of Casey Anthony. And this is what most troubles me about their prosecution of the case:

Why do the prosecutors not want Casey Anthony to be able to put on a defense? Why do they object to almost every witness for the defense and to almost every item of evidence the defense puts forward?

If I were on the Casey Anthony jury, I would resent what seems to me to be the prosecution’s attempt to prevent me from hearing her side of the story.

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Privatize State-Run Crime Labs Now

A commentator on In Session’s Casey Anthony trial coverage recently claimed that if trial attorneys present too much detail about CSI evidence, jurors would likely ignore it all. (Of course, this same commentator claimed earlier that these days jurors expect to hear a lot of CSI evidence.) The Casey Anthony trial likely provides support for both of these claims.


For this one-time criminal-trial juror, the mountain of CSI evidence presented by both sides is beginning to amount to a big yawn. Unlike the In Session commentator who was critical of defense-expert testimony, this endless discussion of post-mortem hair-banding and disgusting fumes rising from a square of auto carpet convinces me that the State of Florida wasted a great deal of taxpayer money on forensic examinations.


Why? To try to convince a jury that they had solid evidence against Casey Anthony—when in fact they do not.


Junk Evidence


In order to develop its forensic-science case against Casey Anthony, the State of Florida found that local crime labs were inadequate to process the mountain of evidence (hairs, fumes, stains, leaves, twigs, fibers, clothes, shoes, shovels, dirt, duct tape, plastic bags, cloth bags, trash, garbage, DNA, body fluids, bones, bugs, stickers, and the lack of same).


So they sent most of this junk to the FBI lab in Virginia and some to a federal research lab in Oak Ridge, Tennessee. The FBI lab costs U. S. taxpayers roughly $8 billion (with a B per year; Oak Ridge National Laboratory, which provides the U. S. with critical research into energy and technology (not merely crime-solving) costs roughly $1.65 billion (less than one-quarter of the FBI Crime lab). The Florida Department of Law Enforcement has an annual budget of roughly $1.4 million (with an M).


For their share of these funds, what have Florida taxpayers received in evidence to prove that Casey Anthony willfully, maliciously murdered her daughter?


1. An Oak Ridge Lab anthropologist’s crackpot theory that the results of a gas-chromatography/mass spectrometry analysis, which showed relatively high levels of chloroform in a gas of unknown origin found in Casey Anthony’s car, was highly suggestive of human decomposition (although an Oak Ridge Lab chemist explained that relative amounts of any chemical in a gas of unknown origin is meaningless, even if in fact chloroform is one of 30 to 80 possible emissions from human decomposition)


2. That only three peer-reviewed studies have been conducted on the gases emitted from decomposing human flesh, and that two of them were authored by an Oak Ridge Lab anthropologist who also believes in divining rods


3. One FBI hair-analyst’s opinion that a single hair found in Casey Anthony’s car was “consistent with” and could not be “excluded from” coming from the head of Caylee Anthony and furthermore that the hair displayed post-mortem hair-banding, which she did not choose to show to the jury by means of photographs taken of the hair


4. Less than a dozen peer-reviewed articles have been published in forensic-science journals on the topic of post-mortem hair-banding



Sidebar: In the thesis (not peer-reviewed article) on hair-banding linked above,  “the author suggests that during the forensic investigator’s examination of a decedent with an unknown PMI [post-mortem interval], a sample of 25 head hairs should be collected and saved for evaluation. The slow decomposition rate of hair, relative to other soft tissues, makes it a valuable source of information in older forensic cases.” Please note that Caylee Anthony’s hair mass found with the skull contained a sample of 25 hairs, but they were unusable for a hair-banding analysis, and the hair found in the car was only a single hair and there was no known PMI.


5. That the FBI lab has an on-going study of whether hair-banding can occur in ante-mortem hairs (that is, hairs from living people) which is so far inconclusive but which has begun to suggest that hair-banding may not be an exclusively postmortem event


6. That the only relevant, usable DNA recovered from any of the evidence was one sample of mitochondrial DNA from a hair, but all that this evidence proved was that females descended from Caylee Anthony’s great grandmother had at some time ridden in Casey Anthony’s car


7. That the FBI lab does not test for “touch DNA,” although it is well-established in Europe


8. That multiple FBI examinations of three pieces of duct tape,  one of which piece was stuck the hair remains, turned up no evidence of anything other than that the FBI lab contaminated the tape on two spots


9. That fly and insect remains found in the car trunk and at the site of recovery showed that flies and insects that are attracted to rotting meat (human and pork) were present. These bugs included “early colonizers” (that is, ones that show up during the early stages of decomposition) and “late colonizers” (that is, ones that show up during later stages). The fact is that Caylee Anthony’s remains completely decomposed—and that’s why nothing but bones and a little hair were ultimately recovered, but there is no CSI proof-positive that anything decomposed in the trunk of the car other than some unknown meat. (The best evidence of human decomposition came from a tow-truck yard operator, not a crime lab.)


10. That a shovel Casey Anthony borrowed from a neighbor was found to have soil on it, but as soon as the remains were found the FBI Lab ceased its examination and never compared the shovel evidence to the soil in the wooded area where the remains were found—so there is no evidence that Casey Anthony borrowed the shovel to bury the body. In fact there is no evidence that Casey Anthony borrowed the shovel to bury anything.


11. That none of the public laboratories found any stains or any substances on anyone’s clothing or shoes. Nothing of evidentiary value.


12. That no fingerprints were found at all.


13. That a bag of garbage from the Anthony car was dried out in order to preserve the organic materials in it, and as a result numerous experts were forced to testify that there were no wet materials or “food” present in the trash when they examined it


14. That a bag of garbage from the Anthony car was odiferous when discovered, but subsequently smelled less strongly after it was dried out.


15. When instructed to search the Anthony family’s computer hard drive (not the defendant’s laptop hard drive), a computer forensics expert on the Orlando police force failed to recover any useful evidence. Then a software developer from Canada recovered a series of searches that took place within a few minutes on an afternoon in March 2008 when supposedly only Casey was at home. No thorough, comprehensive analysis of either hard drive was ever conducted.


I could go on, but it bores me. The fact is that investigators in the Caylee Anthony murder case did not cleverly use CSI evidence to prove what killed her, let alone whodunit.


At this point, the only “evidence” that Casey Anthony did anything wrong is that she lied about her daughter’s whereabouts after she must already have been dead. A reasonable juror would conclude from this that Casey knew Caylee was dead.


But that doesn’t prove how she died.


If the jurors in the Casey Anthony trial have ceased to take notes, this is why. When they retire for deliberations, they will discount most of the physical evidence and be forced to rely on witness testimony. Note that I said “discount,” not “ignore.” The jurors will discuss that fact that for every CSI clue presented, an equally convincing counter was also presented.


And you don’t have to be a Ph. D. to understand this.


It seems to me the taxpayers of Florida would have been better served to have all the evidence in this case analyzed by privately-owned labs, rather than government-owned and run labs, which have an inherent prosecution bias.


 


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Forensic Sciences versus Science and Sciences

The Casey Anthony murder trial highlights the rampant misuse of CSI evidence in American courts. Both sides in the case have trotted big-name forensic scientists to dazzle the jury. Yet little of the forensic-science evidence presented has clarified any of the mysteries surrounding the death of little Caylee Anthony. Only the eye-witness testimony has shed any light on this case.

The problem arises from the term “forensic science.” The word “forensic” in this term means “relating to debate and argumentation.” The “science” in this term is a misnomer like most terms involving the word “science” (such as social science and political science). More apt would be the words “arts” or “craft.” For example, no one would claim to study “legal science,” because all lawyers know that practicing law is an art and craft—a skill, one that varies in quality according to the abilities of each practitioner.

Forensic science provides support for one of the sides in a legal debate or argument. It produces evidence present to bolster an argument, such as: Caylee Anthony had duct tape applied to her mouth and nose, thus suffocating her.

By definition, forensic science can also supply support for the argument that the duct tape was not applied to Caylee Anthony’s face at all but rather to something else, such as the neck of one of the bags found near her remains. Forensic science can even supply support for the argument that the duct tape became stuck to the hair at some point after the remains were dragged around by carnivores. I can think of a very long list of possibilities that forensic science could be used to support.

It isn’t science. Science is the study of nature to discover facts that lead to an understanding of the truth. Science has a specific methodology, which is vastly different from the methodology of forensic science. Science’s methodology begins with the understanding that the truth is not known; a hypothesis about the truth is proposed; and then an almost endless series of experiments is conducted to confirm or deny the hypothesis.

Forensic science begins with an assumption (not a hypothesis). The assumption in the Anthony case is that Casey Anthony murdered her daughter, carried her around in the trunk of her car for several days, concocted a kidnapping tale, then wrapped her daughter’s dead face in duct tape and stuffed her into a plastic bag (or, if that can’t be proven, that she suffocated her daughter with duct tape or maybe by putting her in the plastic bag—although you can’t have it both ways), and then discarded her like trash in a nearby wooded area. All of the FBI laboratory investigators and all of the Orange County investigators proceeded from this assumption to try to find evidence supporting their claims.

But one only bothers to go to the extraordinary effort of looking for a needle in a haystack if you know in advance that a needle is there to be found.

Science is currently looking for a needle in a haystack using the multi-billion-dollar Large Hadron Collider at CERN, a research center in Switzerland. The needle science is looking for is the Higgs Boson, an incredibly small particle that is assumed to exist and must exist if other physics concepts and equations are to be believed to be correct.

Note: I did not say that science and the governments of the world all agreed to spend billions of dollars trying to find evidence to support an assumption. The Higgs Boson is an hypothesis at this point, but it is an hypothesis derived from over a century of scientific research.

In other words, if Casey Anthony’s guilt were a scientific hypothesis instead of law-enforcement assumption, the so-called forensic scientists working on the problem would likely still be working on it until Casey Anthony dies a natural death at a ripe old age.

Unfortunately for American defendants in murder trials these days, no one in the courtroom seems to understand that forensic evidence ought not to be labeled scientific and ought to be understood by everyone—especially the judge and jury—as simply one or two people’s interpretations of a phenomenon they observed.

No amount of forensic science can tell the Anthony jury whether or not the smell and stain in the trunk of Casey’s car was from human decomposition or from pork-chop juices.

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Something smells in the Casey Anthony prosecution

— and I don’t mean the trunk of Casey Anthony’s car.

I’m sorry Judge Perry, but I think you made a mistake by admitting the testimony of Dr. Vass into the Casey Anthony trial.

There appears to be absolutely no way for the defense to assess the results of the tests Vass ran and the conclusions Vass reached, because no one other than Vass has access to the database he uses in his research, including the defense. That means the defense can’t even hire an expert to express an opinion about his conclusions.

Worse yet, Vass’s tests were qualitative rather than quantitative, but nonetheless he expressed opinions about the quantity of certain chemicals in the air sample as compared to other chemicals.

Until I heard the Vass believes in divining rods, the biggest shock in the cross-examination is learning that Vass isn’t a chemist, even though he is testifying about chemicals. He’s a forensic anthropologist. That’s a scientist who studies human remains. But he didn’t test human remains in this case: he tested the gases that were emanating from some pieces of carpeting.

Yes, you read that correctly: Vass believes in divining rods! That means that I was right—the prosecution is presenting superstition as scientific evidence.

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The difference between “scientific instrumentation” and “scientific method”

In the Casey Anthony trial Judge Belvin Perry, Jr., has ruled that the use of gas chromatography—mass spectrometry to analyze the foul odors in the trunk of Casey Anthony’s car is established science and can be admitted into evidence.

And he is right. Right about that, but not about Dr. Arpad Vass’s use of these techniques to draw conclusions about how advanced the decomposition of a human body is based on the mix of gases found in an air sample. His technique relies on a database he collected himself through the use of gas chromatography—mass spectrometry. There are no other scientists attempting to develop a database of the gases emitted by decomposing human flesh, so there is no independent verification of his conclusions.

And multiple independent research studies must be conducted to confirm any scientific theory. That’s what the scientific method is all about.

This is exactly the sort of “science” the Supreme Court ruled inadmissible in the Daubert decision. Vass’s technique and theory are not widely accepted in the scientific community. The doctor himself may be well respected, but that isn’t the same as saying his research is established science. A single database is incapable of being “generally accepted,” by definition.

This trial is my candidate for the worst use of forensics in history. The prosecution is trying to dazzle the jury with “science” instead of presenting solid evidence that Casey Anthony intentionally murdered her child. Even if Dr. Vass can “prove” the smell in her car trunk came from a rotting body, it still doesn’t prove she put the body there or that she killed her child.

Let’s throw Casey Anthony in the pool and see if she floats!

That’s how they used to test witches: if they floated it was witchcraft; if they sunk they were innocent.

On Saturday morning superstition was entered into the trial of Casey Anthony as evidence. Her attorney, Jose Baez, tried to explain to Judge Belvin Perry that “hair banding” isn’t science, but failed. Baez apparently isn’t a very experienced trial attorney and was unable to find legal precedents for his objection to the evidence, but he was right in everything he said.

I’m not a lawyer and certainly not a scientist, but I understand how legal  precedents work (or, as is usually the case, do not) and I also understand the scientific method. There’s very little science in most so-called “forensic science.”

What I am is an expert in reading English language texts, which apparently none of the lawyers in the Anthony courtroom are, or they would have understood the following passage in the National Academy of Sciences report titled “Strengthening Forensic Science in the United States”:

“In cases where there seems to be a morphological match [between hairs] (based on microscopic examination) it must be confirmed using mtDNA analysis; microscopic studies alone are of limited probative value. The committee found no scientific support for the use of hair comparisons for individualization in the absence of nuclear DNA. Microscopy and mtDNA analysis can be used in tandem and may add to one another’s value for classifying a common source, but no studies have been performed specifically to quantify the reliability of their joint use.”

Hair Bands (not the accessory)

On Saturday I witnessed one of the least scientific, most superstitious presentations it is possible for a prosecutor to make: the State introduced an FBI hair-and-fiber examiner to confuse the jury with a nine-inch-long hair that may or may not have been the victim’s and may or may not have exhibited a phenomenon known as “hair banding”—and without even  presenting a photograph to show the jury what the hair really looked like.

Hair banding is nothing more than a discoloration of a human hair near the root. It only appears in some hairs, not all. No one knows what the chemical reaction is that causes the discoloration. Hair banding has occasionally been found in hairs taken from a decomposing human body. When a hair from a decomposing body displays this discoloration, it may or may not be the only hair from that body that displays this characteristic. The hair may or may not still be in its follicle when the banding occurs; the hair may or may not have been pulled out of the body when it occurs; the hair may or may not have fallen out of the body when it occurs. Hair banding “usually” occurs 2 to 4 days after death, according to less than 5 research studies—if it occurs at all.

The FBI witness said she had heard of a banded hair being observed 8 hours after death. She did not tell the jury what the longest time after death she had heard about in which hair banding had occurred—so for all we know it could be weeks or months later, nor do we know yet whether Caylee Anthony’s remains included any banded hairs. Or any hairs at all, for that matter.

And, if I’m not mistaken, the FBI expert said that the lone hair in question was the first hair she had ever examined when she did not know what body it had come from. In other words, all the other banded hairs she examined were plucked from or had fallen from a KNOWN DEAD BODY!

Let me be clear about this: the FBI expert had previously expressed an opinion about hair-banding only when she knew for a fact whose body it had come from.

She has only used banded hairs for purposes other than to claim a specific dead body had been in a specific location. (In other words, she had never used hair analysis to identify a dead body.) The Anthony case is the first time she ever did what she did.

In the Anthony case, a hair found in a specific place is suspected of coming from a dead body, but the FBI expert can’t tell which dead body it came from. The prosecution doesn’t know whose dead body it came from. It’s a hair that looks similar to hairs found in Caylee’s hair brush. But the FBI expert has always before studied hairs from known corpses in the custody of the authorities. (In fact, Baez tried to introduce testimony about a case in which another FBI expert mis-identified a banded hair using this same faulty methodology, which resulted in a false conviction, but the judge didn’t seem to understand this, and Baez wasn’t able to make it clear.)

Sidebar: Much as I admire Judge Perry, several times in this trial I have observed him to mistake scientific instrumentation for scientific method. (More about that later.)

There is no scientific data about such discoloration occurring in hairs pulled or fallen from living human bodies. You heard me right: no scientist, forensic or biologist, has ever researched the possibility of living people shedding hairs which subsequently display hair banding. None. No “peer-reviewed journal articles.” Given the gazillion hairs out there today on Planet Earth, the odds are, folks, that a living person’s hair has at some time discolored once it left its nurturing, little follicle.

The fact is, forensic science does not know whether hair banding is a phenomenon exclusive to human decomposition or not.  They cannot say whether hair banding occurs in all mammals. And until they figure out what the chemical process is that causes hair banding, they cannot even say whether it is a real process or just a random event—and random events do occur in nature.

But don’t confuse the FBI alchemists with logic.

The discoloration of that nine-inch hair, which forensic “scientists” call “hair banding,” is actually the least of the logical fallacies I heard presented by the FBI expert and the prosecutors during Saturday morning’s testimony, but in this blog I want to focus on it, because Baez raised issues taken from the above National Academy of Sciences report on the failings of forensic science and its misuse in court. This report should be studied by every criminal court judge and every trial lawyer.

In 2009 the National Academy of Sciences (which is something like a standards board for the scientific method) issued a report warning the justice system in this country of abuses of forensic science as evidence in trials. The report stressed the value of DNA evidence, when properly used, and the fallaciousness of many other forms of forensic evidence, especially “hair and fiber” evidence, for which there are no analysis tools. (Using a microscope to peer at a hair is not an analysis tool; it is a tool of art and craft; its value is entirely dependent on the skill of the observer. Real scientific instrumentation does the job itself and prints out a report—I’m also an expert on this because I was once an editor for The Astrophysical Journal.)

In other words, hairs and fibers can be chemically analyzed, but all that such chemical analyses will tell an investigator is that a hair is a human hair and a fiber is a fiber of one type or another. No scientific analysis can tell a jury that a given hair came from a given person unless the hair root contains nuclear DNA. Mitochondrial DNA (mtDNA) can be u
sed to tell whether the hair came from a person with a specific matrilineal ancestry. In a case such as the Anthony case, a hair root might be able tell whether or not the hair came from Caylee, Casey, or Cindy, or even Cindy’s mother, but not which one of them it came from. Logically, though, if the hair had been colored or chemically treated, that would rule out Caylee, but not the adult women.

But the nine-inch hair did not have sufficient root present to contain any DNA—therefore, there is no scientific way to prove it came from the victim in this case.

It ought not to have been used as evidence before the jury, if you understand the NAS report.

By now it should be obvious that I don’t believe there’s sufficient evidence to convict Casey Anthony of murder. However, from listening to the jury voir dire in this case I also don’t think there’s anyone on the jury who will understand how bogus this hair banding evidence is. Nurses are not scientists, although they probably think they are. At this point, the defense has to hope that someone on the jury will understand all the other illogical assumptions the prosecution is making about this lone hair among all the other hairs found in the Anthony car and about the car itself. (There’s at least another blog to be written about those absurdities, too.)

Reread the above statement taken from page 161 of the NAS report: There is no scientific literature (peer- reviewed journal articles) that says it is possible to identify a person using a lone hair without so much as mtDNA. Let me make this even clearer: no scientist would bother to use a microscope to compare hairs if he or she did not also have DNA samples for confirmation.

Yet the Anthony jury heard testimony that such a hair was consistent with Caylee’s hair and could not be ruled out as possibly being Caylee’s hair—that’s identification, folks.

If were Jose Baez, the first witness I would call in the defense case would be a member of the National Academy of Sciences whose expertise is in the scientific method.

MADD about Florida DUI Enforcement

The Leyritz DUI manslaughter trial has convinced me that Florida law enforcement doesn’t have a clue about how to prevent drunk driving.

Sidebar: MADD (Mothers Against Drunk Driving) has done infinitely more to prevent drunk driving deaths than any cop or prosecutor in the world. Please visit the website and support their efforts.

Another Jury in the Dark

Over the past couple of weeks, a jury in Ft. Lauderdale, FL (famous for Easter Break binging), has heard only half the story of how a young woman died in a collision at an intersection in what the lawyers are euphemistically calling the “Entertainment District.” Apparently the only entertainment in Ft. Lauderdale is drinking.

The full story is that two drivers who had been drinking for several hours happened to reach the center of an intersection at exactly the same time. One of them obviously had a red light and the other obviously had a yellow light when they entered the intersection. Both drivers were over the speed limit at least slightly at the instant they collided. The driver wearing his seatbelt survived with a mild concussion. The driver without her seatbelt was thrown from her vehicle and died a grotesque, bloody death.

The survivor was arrested and held for several hours before the cops took a blood sample from him. Then an hour later they took a second blood sample from him, for reasons that have not been discussed before the courtroom cameras. He was then charged with DUI manslaughter. The victim’s blood was tested at the time of the autopsy. The blood-alcohol content levels (BAC) of both drivers were well over the legal limit of 0.08: the survivor’s BAC was discovered to be 0.14 and then 0.13 an hour later; the victim’s was 0.18 at the time she died.

What the Jury Heard

Through errors on the prosecution’s part, the fact that the victim of the crash as well as the survivor had been drinking came out in court. The jury also heard that the victim’s BAC was definitely 0.18 when she died (and that’s over twice the legal limit). The jury also heard that the defendant-survivor’s blood was drawn once three hours after the crash and that it tested at 0.14.

I believe any juror would assume that BAC levels go down and therefore the defendant’s BAC at the time of the crash had to be much, much higher than 0.14.

But It’s Less then Half the Story

But I now know that this is not true: BAC levels go up dramatically for a period of time after drinking. And both parties in the accident had taken drinks only a few minutes before the accident. And apparently the law that sets the legal BAC limit in FL at 0.08 applies only to the exact moment when the accident occurred.

So, any juror who assumes that a BAC sample drawn after an accident reveals the relevant BAC level (that is, the degree of inebriation) is mistaken. Experts in alcohol toxicity for both sides in the Leyritz case testified that the BAC level rises dramatically minute by minute and then falls slowly.

Not only that, but the cops in the Leyritz case completely bungled the DUI tests at every stage in the investigation:

  • At the scene an “expert” in the Field Sobriety Test administered it to Leyritz without taking into consideration that he might have a concussion from the collision. He concluded that Leyritz was over the legal limit as a result.
  • When Leyritz told the officer his lawyer had instructed him not to take the breathalyzer test, the officer then compelled him to submit to a blood test. But—duh—the paramedics at the scene were too busy trying to save the victim’s life to draw blood from Leyritz (this was at least 15 minutes after the collision—already too long after it to get an accurate reading, according to the experts).
  • So, the officer took Leyritz to a police station (I believe it was) where he asked an EMT to draw the blood. The EMT apparently tried several times, but couldn’t “get a stick” in his arm. (Since I’ve had this happen to me, too, I know it’s very painful. Not a BAC test, though!) During this process, the EMT rubbed alcohol on Leyritz’ arm several times. (Yes, I know alcohol evaporates rapidly in the air, but a small amount enters the arm at the puncture point, and small amounts is what the test is all about.)
  • Next, three hours after the collision, the officer took Leyritz to a hospital emergency room. According to the officer this was because he needed a nurse to draw the blood. According to the defense, it was because Leyritz was complaining of whiplash. After again wiping his arm with alcohol, the nurse was successful in drawing his blood using the cop’s supplied BAC test kit. She apparently “inverted” the test tube an inadequate number of times to mix the preservatives in the tube with the blood. This was the 0.14 BAC level.
  • For some unspecified reason, the officer ordered a second blood test an hour later (during which the nurse again wiped his arm with alcohol). This was illegal, but he did it anyway. The judge threw it out of court. The jury never heard about it or they would have learned that four hours after the collision, his BAC was going down (0.13).
  • However, the blood samples weren’t delivered to the toxicology lab for several more hours, and when they finally were dropped off, they were left in an unrefrigerated bin for several more hours before they were finally tested.
  • Since the samples were taken using a kit that wasn’t approved for BAC testing (it had insufficient preservatives), there was a good chance that the blood began to deteriorate in the intervening hours. This deterioration process was literally a fermentation process in which microbes (not bacteria, although the prosecutor didn’t know there was a difference) break the blood down and produce ethanol alcohol as a byproduct. In other words, by delaying the tests the cops probably increased the BAC.
  • The prosecution didn’t understand that the second blood sample was illegally obtained, because they had an expert witness extrapolate the defendant’s BAC at the time of the collision based on the decrease in the levels from the first to the second test. He calculated that the defendant’s BAC would have been 0.18.
  • After the judge excluded the second sample, the expert recalculated the BAC using some sort of standard model (I believe I heard someone say it was developed in the 1930s!). This time he concluded the defendant’s BAC would have been 0.196. And this is what the jury heard.
  • The defense expert, however, ran several models, all based on the first test’s result of 0.14. He took into account a wide range of factors that the prosecution expert completely ignored, including the defendant’s stomach contents, Body Mass Index, possible traumatic brain injury, etc. From his models he found that the defendant’s BAC at the time of the accident could have been as low as 0.04, was likely 0.07, but could have been 0.08 or slightly higher—but under no circumstances was it at all possible that the BAC was 0.196. And he explained why very clearly: the prosecution’s model assumed that all the drinks were consumed at one time, just minutes before the accident, producing an immediate spike in BAC and then that the BAC steadily declined for the next three hours.

Since it’s impossible for all these conclusions to be correct, what this trial tells me is that the state of the art of detecting blood-alcohol levels in accused drunk drivers is co
mpletely inadequate for justice
to be administered based on blood tests. It wouldn’t matter if the cops had handled Leyritz’s blood tests properly: the experts would still disagree about the proper model for analysis.

 

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Jury Fed Junk Science Again

On Tuesday the jury in the Jim Leyritz DUI manslaughter trial sat through hours of junk-science testimony from the head toxicologist of Broward County, Florida. The tale of how his testimony was admitted into evidence is as bizarre as what he told the jury.

Blood Alcohol Level Calculation

If anything should be well-established forensic science by now, a juror would expect blood-alcohol analysis to be it. So jurors in the Leyritz trial are likely to believe what the toxicologist told them yesterday.

Once again, we should all be thankful we aren’t on this jury. Because I’m not a juror in the Leyritz trial I heard the legal arguments about the evidence. I know the toxicologist’s testimony is evidence only of the shoddy nature of forensic toxicology.

It seems the cops drew two blood samples from the defendant, an hour apart (3 and 4 hours after the accident). Based on the differences between the two samples, the toxicologist determined the defendant’s metabolism rate and then extrapolated what his blood-alcohol level must have been at the time of the accident: about 0.182.

However, Judge Marc Gold ruled that the second blood draw was illegal; as a result the prosecution could not ask the toxicologist about the extrapolation he made based on the second sample.

Specifically, Judge Gold asked the prosecutor whether the toxicologist had “relied exclusively on” the second sample for his opinion or whether he could render an opinion without relying on it. The prosecutor (a young woman who frankly seems clueless) said he could; he had another “calculation” he could use.

Clearly the judge expected the toxicologist to testify that the blood-alcohol level was somewhere around 0.182 based on this new calculation; but, alas, he testified that the level was about 0.196, a difference of 0.014.

Judge Gold has previously ruled in this trial that plus or minus 25% is unacceptable in statistics, at least with a sample size of 3 blood-alcohol levels (0.04, 0.06, and 0.08) In this instance, he has only two numbers to evaluate (which makes it impossible to determine what the real margin of error is)—and I don’t mean 2 blood samples, I mean 2 blood-alcohol levels (0.182 and 0.196). There’s a 0.014 difference (14 points).

In other words, there’s no way of telling how accurate or inaccurate either of the numbers is.

Junk Science

What this proves is that either the method used by toxicologists to calculate the rate at which alcohol is metabolized based on two samples is wrong or the method used to extrapolate the level of blood alcohol at a given past time based on a sample is wrong.

If so, then there needs to be substantial reform in DUI forensic toxicology.

The Judge and the Jury

It will be interesting to see how Judge Gold handles this.

It seems to me (and I am not a lawyer) that he has several issues to resolve:

  • The prosecutor did not understand what he meant by asking her if the toxicologist relied exclusively on the second sample for his opinion, and as a result she allowed the toxicologist to introduce into evidence an entirely new opinion, which the defense had never before heard.
  • The defense did not know the calculation generally used to extrapolate a prior blood-alcohol level, or they would have anticipated that the toxicologist’s new estimate would be much higher than his first estimate.
  • The toxicologist’s change in his testimony reveals the gross flaws in the whole “science” of DUI toxicology.
  • The problem is that the defense can’t cross-examine this testimony and show the flaws, because the judge (at the defense’s request) has excluded the second blood sample.

Of course, it may simply be that in the ten minutes the toxicologist was given to calculate a new estimate, he made a math error.

Hoist on their own petards! All of them.

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