Two murders rocked Noxubee County, Mississippi, in the early 1990s. In each case, a young girl was abducted from her home, raped, murdered, and then dumped in a nearby body of water. Although the cases were startlingly similar, a different man was accused of each crime. Even though he had an alibi, Levon Brooks was pegged for killing 3-year-old Courtney Smith, based on the fact that he’d previously dated Smith’s mother. Kennedy Brewer was charged with the murder of 3-year-old Christine Jackson, whose mother he was dating.
The state’s case against each man was based on the findings of Steven Hayne, Mississippi’s de facto medical examiner, and Michael West, a dentist and self-styled bite mark expert. In each case, Hayne identified what he believed to be bite marks on the victim’s body and referred the evidence to West. This was not unusual. For decades, Hayne and West worked in tandem as the go-to experts for police and prosecutors in Mississippi.
The doctors were unequivocal in court about the medical evidence. At Brooks’s trial, West told the jury that “it could be no one but Levon Brooks that bit this girl’s arm.” In Brewer’s case, West pulled out one of his signature lines, saying that marks found on the victim’s body were “indeed and without a doubt” made by Kennedy Brewer. Brooks was sentenced to life in prison. Brewer was sent to death row.
But Hayne and West were wrong. Brooks and Brewer were innocent. Instead, a man named Justin Johnson, who had a history of committing similar crimes, was responsible for both murders. Eventually, DNA would tie him to the murder of Jackson and he would confess to killing Smith. He denied biting either victim.
Brooks and Brewer were wrongly convicted based on questionable bite mark “science,” which has been implicated in more than two dozen wrongful convictions or indictments nationwide.
Perhaps no one in the country better represents the dangers of junk forensics than West and Hayne, who turned themselves into jack-of-all-trades experts and made extraordinary amounts of money by dominating the state’s forensic death investigation system — Hayne did three-quarters of the autopsies in Mississippi, an impossible workload. The pair sent countless people to prison, and, in some cases, allowed killers like Johnson to go unpunished for years.
But what happened in Mississippi is not unique. Forensics scandals have erupted across the country, while reports like those from the National Academy of Science in 2009 and the President’s Council of Advisors on Science and Technology in 2016 raised serious concerns about the validity and reliability of a host of forensics practices used for decades to send people to prison. Few — if any — of those concerns have been addressed, yet the Trump administration has basically turned its back on forensics reform, while courts across the county continue to allow questionable forensics into evidence.
In an interview with The Intercept, Balko and Carrington explained why certain forensics are little more than junk science, how the courts vet supposedly scientific evidence, and how Hayne and West navigated this system to their benefit — leaving a devastating legacy in their wake.
I figure we can start out with the basics. What is bite mark matching?
Radley Balko: Bite mark analysis is when a forensic analyst looks at bite marks on a body — either the body itself or sometimes even in photos — and attempts to match them to the dental mold taken of a suspect. But it rests on two flawed premises. The first is that human dentition is unique — that we all leave a different kind of bite. There’s just no scientific research to back that up. And the second premise is that human skin is capable of recording bites in a way that preserves the kind of detail that can distinguish one person from another. Not only is there no scientific research to back that up, the research that has been done suggests that this isn’t the case. And, if you think about it, it’s pretty intuitive. Human skin is soft, spongy; people start healing immediately after a wound is inflicted; and people heal at different rates.
And in two cases we write about in the book, the little girls were exposed to the elements, they were submerged in water. One of them had been embalmed. So the idea that you could find these tiny, almost microscopic details in these wounds that you could trace to small little facets of someone’s teeth, to the exclusion of everyone else, is just absurd.
Bite mark analysis is just one of the pattern-matching forensic practices. Tell me how they relate to each other in terms of whether there is any real science underpinning them.
RB: Pattern matching in general is just what it sounds like. It’s where an analyst will look at evidence from a crime, or an alleged crime, and then look at another piece of evidence that ties that crime to a suspect. So it could be hair fibers found at the crime scene versus hair taken from a suspect, or carpet fibers from a crime scene and comparing them to carpet fibers found on the shoes of a suspect. And they basically just eyeball it. There’s no calculation to be done, there’s no margin for error. It’s entirely subjective.
In the pattern-matching disciplines, you regularly get defense and prosecution experts who give contradictory testimony. And then it boils down to who’s better at persuading juries. Who’s more charismatic, who’s more persuasive. And usually, the skillset it takes to be persuasive on a witness stand isn’t necessarily the same skillset it takes to be a sound and scientific analyst. And that’s really part of the problem.
What is the standard for deciding whether this stuff is allowed into evidence? How is it supposed to work, and how does it work in practice?
Tucker Carrington: There was a case which lasted the better part of the 20th century out of the D.C. Court of Appeals called Frye. And essentially, Frye said it was the “general acceptance” theory, which is that if a scientific discipline or expert opinion was generally accepted in a given field, then it was presumptively admissible. In the 1990s, a case by the name of Daubert v. Merrell Dow Pharmaceuticals was heard in the U.S. Supreme Court, at about the same time that the federal rules of evidence were changed — Rule 702, which is the rule for admission of expert testimony.
The feeling was that the “general acceptance” test could be too narrow. There were theories which, for all kinds of reasons, hadn’t gained general acceptance but were nonetheless valid opinions. They had scientific bases. And so the court in Daubert essentially tracked and validated the recently adopted Rule 702 and said, we’re rejecting the Frye test; it doesn’t have to be generally acceptable, but it does have to meet a nonexhaustive set of criteria [e.g., whether the theory or technique had been and could be tested; whether it had been subjected to peer review; whether there was a known error rate].
And then, what the Supreme Court did was essentially made — and this is the term of art that people know — it made trial judges “gatekeepers” of this type of evidence. It was the trial judge who had to sit and listen to both sides argue for the admissibility or inadmissibility of the evidence. If the evidence met the listed nonexhaustive criteria, it would be admissible, and if not, not. So, in a nutshell, that is the standard. There are a few states that still use the Frye standard, but most states and the federal courts use the Daubert v. Merrell Dow standard.
Is it working to keep junk science out of court?
RB: It isn’t working at all. It does sometimes work in civil cases, where both sides tend to be pretty well funded and judges will sometimes even hire a person to educate the court on given issues. In criminal cases, you just don’t see the same level of skepticism. And it’s entirely predictable, right? We’re asking judges who are trained to do legal analysis, and that’s what they’ve done their entire lives, and we’re asking them to now suddenly do scientific analysis.
And when it comes to the scientific analysis, they’re doing it exactly like you would expect judges to: They look at precedent. And that isn’t how science works, right? Science is always questioning the past and revising theories and changing things based on new knowledge. Whereas the courts strive for consistency and finality, so they’re always looking to what other courts have done, partly just as an ass-covering measure. If you’re a judge and you don’t really know the science very well, an easy thing to do is look to see what other judges have done, because if other people have done it too, nobody’s gonna call you out for doing it. When a particular brand of forensics isn’t scientific, there’s a strong incentive for a judge not to call it out, because they’re going out on a limb.
TC: I think one dynamic that should be highlighted, because it occurred in the Brooks and Brewer cases, and frankly, almost every bite mark case I’ve read, is that when the prosecution announces that it has a bite mark expert, to the extent that there’s a reaction, the defense reflexively goes out and hires its own bite mark expert.
The problem there is they already missed the boat, because when you allow a state expert to come in and offer up testimony, then you allow the defense to do the same, you’ve validated the discipline. And as you know, the problem with some of these disciplines is they are not valid. What should be happening is if the state announces it has an expert in whatever discipline, the defense says, I’m not gonna hire a bite mark expert because even my bite mark expert, if he or she wants to continue testifying, is gonna say, “Oh, no, this is a valid discipline! It just turns out that other person’s opinion is wrong.”
No, what you need to do is hire someone at a university who teaches the history of science. And they come in and say, here are the fundamental constructs of a valid science: error rate, testability, reproducibility, peer review, et cetera, whatever it happens to be. And this discipline doesn’t meet it.
Left: Hachette Book Group. Right: Kevin Bain via Hachette.
A lot of forensic practitioners use the same line: “We’re not a bench science, we shouldn’t be held to those standards.” But then, how can you ever know whether what they’re peddling is valid, reliable? They try to set themselves apart, but you can’t call something science that isn’t science, right?
TC: It’s like saying, well, I’m not a science-science, I’m just a science. If that’s your jam, then go with it. But it’s not admissible as evidence. It’s like dowsing rods. I’ve seen dudes use them, and they found the sewer line outside my house, so, whatever. But it’s not admissible.
RB: It’s just a way to define them that means that the only people who are allowed to criticize them are the people who already believe in their methods. If you’re going to study the scientific validity of palm reading, you’re not going to have your committee that’s doing the investigating staffed with palm readers. You’d have it staffed with scientists. It’s like, to define yourself as a soft science, you get to create the very criteria by which the legitimacy of your field is measured. And that’s a huge problem.
So tell me, who is Michael West and who is Steven Hayne?
RB: Steven Hayne was a medical examiner in Mississippi from about the late ’80s through the late 2000s. For most of his career, he did autopsies for prosecutors. He actually never held an official position in the state; instead, he was a doctor in private practice.
What would happen — and this is the way the coroner system operated in Mississippi, basically since Reconstruction — is that if there’s a suspicious death, the county coroner would take the body to a private medical examiner or doctor. They pay a fee to the private doctor, and the doctor comes back and says, here’s the cause and manner of death. Well, the problem with that system — whether you have corrupt prosecutors who are out to get convictions at any cost, or just prosecutors who have a general hunch about how a crime happened — if you were a medical examiner and you come back and say, no, that’s not how it happened, you’re making the prosecutor’s job more difficult. It makes it harder for them to get a conviction. So, you may not get the next referral. Whereas the doctor who plays ball and tells prosecutors what they want to hear is probably going to get more referrals.
And so, basically, whether you had prosecutors who were brazen and explicit about pressuring doctors to give them what they wanted, or it could be as simple as a prosecutor who’s going with the doctor who makes his job easier, it was a system that selected somebody like Dr. Hayne. Hayne, over the years, developed this reputation as a guy who would tell prosecutors what they wanted to hear. My impression is that he has a very high social IQ; he’s able to read people and respond accordingly. He was arrogant but not particularly brazen about his arrogance. He usually left himself some wiggle room. He would give prosecutors just enough that they could make their case to the jury, even if what they were running with was not scientifically sound. Hayne would give them enough to run with, but also maintain plausible deniability if he were ever called out on it.
Over the course of his career, Hayne did about 75 to 80 percent of the autopsies in Mississippi, for the better part of 20 years. And in raw numbers, that shakes out to, by his own admission, somewhere between 1,500 and 1,800 autopsies per year. To put that into perspective, the National Association of Medical Examiners says you should do no more than 250-ish autopsies per year. So, Hayne was just blazing new trails. And he was doing all his autopsies from this morgue at night, which lent this macabre and gruesome reputation. We’ve talked to people who said that they saw them smoking cigars and eating pork sandwiches while they were conducting autopsies.
TC: Dr. West trained as a clinical dentist, and he got into this field, he says, because he was in the Air Force and was asked to use his dental expertise to identify the remains of airmen who had died in plane crashes. When people talk about forensic odontology, that’s generally what they think of: After a plane crash or car crash or a fire of some type, when a body is burned or destroyed beyond recognition, you can sometimes figure out identity through dental records. That’s how he got his start. He’s a garrulous, outspoken, sort of back-slapping, thick-accent Mississippian. And he began to take his skills as an investigative dentist that he had started honing in the Air Force and turned them to other pursuits. Among them, at least at first, was his ability, he said, to match pattern evidence that was made by teeth to the dentition that made them.
He began to make a name for himself. He and Hayne became associated with one another, and really became colleagues. West worked with Hayne on autopsies. They advertised in some trade magazines and by word-of-mouth and became this pair that prosecutors went to, to solve and/or prosecute some of these serious cases. The other thing that West did was, over time, he began to expand his areas of expertise. And we list several of them in the book. They ranged as far afield as in an Ohio case where a child had been injured, and may have died, from a bleach accident or incident. West claimed that this wasn’t an accident, that somehow he could tell by the way the bleach had been poured that it was purposeful.
That’s not uncommon among forensic practitioners, to dabble in multiple things. But when that is allowed to happen — when you have a practitioner who is dabbling in fields of questionable science, and ones that we can say have no scientific underpinning at all — what do you think that says about forensic science as a whole?
RB: I think there’s a general public misunderstanding about what forensics is. CSI shows have also contributed to this. Everyone’s an expert in everything. And it just doesn’t work like that, but the problem is that, because there aren’t good governing bodies within different fields of forensics, if you have somebody who is willing to tap into the public ignorance about all these various disciplines and fields, they can do a hell of a lot of damage.
One of the cases that I think really illustrates this point is a case we talk about in the book where Hayne testified as a blood spatter expert. Blood spatter is already a questionable field, but even if you accept it, there’s no reason why a forensic pathologist, a medical examiner, would be an expert in blood spatter. That’s physics, not medicine. Yet the court lets him testify, and again, the reason is because other courts have already let him do it. Then he testifies that the blood spatter on the wall suggests that the victim was moving in a defensive manner as opposed to an aggressive manner, so therefore, the defendant’s claim that he was acting in self-defense was wrong. Turns out, it’s not even clear that that it was blood on the wall. Because it was never tested to see if it was blood. And so, basically, Hayne’s analysis was based on photos of discoloration on a wall.
West was just an egregious example of this. He was paid to be an expert in everything from video enhancement to pour patterns and all sorts of different pattern-matching disciplines. He claimed to be an expert in identifying fingernail scratches and matching them to somebody’s specific fingernails.
How do court rulings embolden people like West and Hayne? How are they supported in what they did by the way the courts treated these various areas of forensics?
RB: By giving it credibility as being presented before juries as science, or at least a veneer and gloss of science.
It’s very, very difficult to find any forensic disciplines at all that have been rejected by courts. We do talk about one in the book, which is an amazing juxtaposition, in a case where Hayne claims that he could tell by bullet wounds that there were two people holding the gun that fired the bullets. That’s an absurd thing to say, and the defense challenged him. And the judge in that case rejected the challenge. He didn’t even hold a Daubert hearing, just rejected it outright. Later, the defense wants to call an expert in false confessions, a woman who had studied false confessions and found that the kid in this case, who was 13 years old and being tried as an adult, met a lot of the criteria for false confessions. The prosecution objects, and the judge holds a one-day Daubert hearing. He hadn’t held a Daubert hearing on Hayne or West — nobody had held one for their entire career in Mississippi — but he’s going to hold one on false confessions. And in the end, he rules that there’s not enough scientific research to support the idea that people falsely confess to crimes.
It was just an amazing illustration of how farcical these Daubert analyses really are.
Are these issues unique to Mississippi?
TC: Mississippi is not an outlier. The systemic issues that exist here are reproduced in other states. Who the persons are that end up peopling the stage may be different. They could be rogue, corrupt cops as opposed to a rogue, corrupt forensic expert. In other words, the pathogens are different, but the host body has some of the same problems.
RB: We’ve seen these scandals all over the country. I think there are aspects of this story that are uniquely Mississippi, just in the way the state has reacted. A lot of other states, when they had a huge forensics scandal like this, assembled some sort of panel to do a thorough review, and there’s been some sort of effort to assess and correct the damage done. In Mississippi, that just hasn’t happened.
What are the implications of that?
RB: The implications are, frankly, pretty depressing. Because I don’t think anyone is going to have the courage — anyone in authority — to give this story the recognition it deserves.
When you let bad science into trials, then somebody gets convicted, and then good science later comes along and proves that the bad science was bad, the courts don’t adjust to that, because the law wants finality. It’s allegedly to protect the integrity of the system, because if we let verdicts be overturned willy-nilly, then people are going to start to lose faith in the system. But if you’re not overturning verdicts that need to be overturned, the integrity of what you’re protecting is superficial.
What’s the big takeaway from this story for you?
RB: Let me answer it as what do we hope this book will accomplish. I think on a very practical level, but also probably not realistic, there needs to be a thorough review of every case in which either Hayne or West participated. There needs to be an assessment of the damage done, and some sort of reckoning to try to right what can be righted at this point.
In my most optimistic mind, I would hope that maybe the book is a warning, a cautionary tale that we need to change how we evaluate the scientific merit of expert testimony. There are new fields of forensics emerging almost daily. A lot of them are just as preposterous as some of the stuff that West was claiming. DNA testing should’ve been a wake-up call that we’re doing some of this stuff wrong, that the way we process what is and isn’t science is wrong. But it really seems we haven’t learned that.
This interview has been edited for length and clarity.
Disclosure: Radley Balko, co-author of “The Cadaver King and the Country Dentist,” is married to a member of The Intercept’s staff.