Check out the latest Popular Science magazine article titled “It’s Time To Treat Crime Forensics Like Real Science”.
January 18, 2012 — In a case that could open an inquiry into the scientific validity of bite mark evidence, two Illinois dentists are suing an expert odontologist for allegedly defaming them after he used a rape case they testified at as an example of how bite mark evidence can lead to wrongful convictions.
Russell Schneider, DDS, of Waukegan, and Carl Hagstrom, DDS, of Fox Lake, filed their lawsuitagainst Ventura, CA, dentist C. Michael Bowers, JD, DDS, in November 2011 in Cook County Circuit Court.
The lawsuit claims that Dr. Bowers used a case they worked on as proof that the forensic discipline is scientifically unreliable.
— Jed Stone, attorney
Dr. Bowers is a clinical professor at the University of Southern California Ostrow School of Dentistry in Los Angeles and has written several forensic dentistry books, including Forensic Dental Evidence: An Investigator’s Handbook. He also co-authored Digital Analysis of Bite Mark Evidence. He has been a dentist for 36 years and is certified by the American Board of Forensic Odontology and as a crime scene analyst. He also serves as a deputy medical examiner for the Ventura County Medical Examiner’s Office.
In February 2011, Dr. Bowers, who lectures frequently, gave a presentation titled, “A Perfect Storm: Is There a New Paradigm to Keep Bitemarks Afloat or Will They Sink?” at the annual meeting of the American Academy of Forensic Science. According to the lawsuit, he included in that talk a case that Drs. Schneider and Hagstrom had worked on in a list of 10 wrongful convictions caused by bite mark evidence. They allege that this action subjected them to ridicule and a loss of business.
The case Dr. Bowers referenced involved Bennie Starks, who was convicted in 1986 of beating and raping a 68-year-old woman. Drs. Schneider and Hagstrom examined evidence for prosecutors in the case and testified at trial that Stark’s teeth matched a bite mark on the woman’s shoulder.
Starks was sentenced to 60 years in prison but always maintained his innocence. In 2006, after serving nearly 20 years, an Illinois appeals court granted Starks a new trial after DNA tests excluded him as the source of semen on the victim’s underwear.
The appellate court did not rule on the bite mark evidence. But subsequent forensic analysis of Drs. Schneider and Hagstrom’s opinions by Dr. Bowers and other odontologists concluded that their work was flawed, according to Jed Stone, Starks’ attorney. Specifically, they found that Drs. Schneider and Hagstrom reversed the upper and lower molds of Starks’ teeth, confusing one for the other, in their examination.
Drs. Schneider and Hagstrom did not respond to requests by DrBicuspid.com for comment; Dr. Bowers declined to comment.
Bite mark analysis criticized
Bite mark testimony has been criticized by some courts for its lack of a scientific foundation, essentially leaving dentists to compare by visual examination bite marks on a victim’s skin with x-rays or molds of a suspect’s teeth to determine if they match.
“Drs. Hagstrom and Schneider incorrectly identified photographs of alleged bite marks on the victim as coming from Mr. Starks,” Stone told DrBicuspid.com. “We now know two things. One, they were wrong. And two, their bite mark opinion, introduced by the prosecution at Mr. Starks’ trial, contributed to his wrongful conviction.”
A Congressional hearing in 2009 focused on the findings of a National Academy of Sciences report on the scientific basis of forensic disciplines. Among the pattern evidence fields reviewed in the report, bite mark analysis received critical commentary. During the hearing, legislators heard from another man who, like Sparks, was wrongfully convicted on bite mark evidence and later exonerated through DNA analysis.
In addition, a 2009 study published in theJournal of Forensic Sciences (July 2009, Vol. 54:4, pp. 909-914) challenged the commonly held belief that every bite mark can be perpetrator identified. The results indicated that when dental alignments were similar, distinguishing which set of teeth made the bites was difficult. The researchers cautioned that bite marks should be very carefully evaluated in criminal investigations in which perpetrator identity is the focus of a case.
The study’s lead author, Raymond Miller, DDS, a clinical associate professor of oral diagnostic sciences at the University at Buffalo’s Laboratory for Forensic Odontology Research in the School of Dental Medicine, noted that numerous cases have been overturned through erroneous interpretation of bite marks. Dr. Miller warned of the dire consequences caused by such misidentification for the accused, the victim, and the justice system.
“We know that forensic odontologists are excellent at identifying human remains from dental records,” Stone said. “We know that the science is far less reliable when dentists attempt to identify bite marks on elastic skin surfaces. And we know that whatever reliability there is, it is far less reliable still when done only from photographs.”
The current suit claims that Dr. Bowers’ presentation constitutes “false publications” because the reversal of Starks’ conviction was not due to faulty bite mark testimony. It claims that Dr. Bowers imputed that Drs. Schneider and Hagstrom “lack ability and integrity” as forensic odontologists.
The alleged defamation harmed the professional reputations of Drs. Schneider and Hagstrom, the complaint contends. They have not been retained to provide bite mark testimony in any cases since then, and the number of patients that have been referred to them for treatment and evaluation has decreased, according to the lawsuit.
In a defamation suit, the plaintiff must prove that the alleged defamatory statements are false. If it goes to trial, the case could open an inquiry into the scientific validity of bite mark evidence.
The suit seeks compensatory damages as well as legal costs.
Prosecutors still have not decided whether to retry Starks.
Witnesses worked on rape case in which defendant was granted a new trial because of DNA evidence
In the ongoing battle over the use of controversial bite-mark evidence, two Chicago-area dentists have opened a new legal front, suing a colleague for alleged defamation because he used a Lake County rape case they worked on as an example of the oft-criticized discipline gone awry.
Dentists Russell Schneider, of Waukegan, and Carl Hagstrom, of Fox Lake, filed their lawsuit against Michael Bowers, a dentist in California who is a frequent and sometimes acerbic critic of his fellow forensic odontologists for work that has led to numerous wrongful convictions.
Let’s think for a moment concerning what our wish list would be for bitemark analysis, our profession’s only controversial subject. I would start with an admission and publication from the ABFO of the noted and significant weaknesses that exist at this time in the field. Inferring from its contents, the ABFO’s Guidelines and Standards imply that all things have not been going well. This document expresses some technique recommendations and establishes a few limits on the behavior and language used by forensic dentists. It is not comprehensive since it is silent regarding the scientific basis of dental “uniqueness” determinations by our membership, but its intentions are good and progress is being made. Now is the time to analyze the basic weaknesses and failings of this field’s scientific underpinnings. This article is a short discussion of the biggest weakness and contains a suggestion to minimize the current high degree of risk that exists when bitemark analysis is presented in court.
Taking a historical viewpoint, the early (Texas, 1954)(1) acceptance of bitemark analysis by the U.S. appellate courts really proved a disservice to all participants and future trials. For the sake of this discussion, discount the apparent details of the cases like Marx(2) (California, 1975) which generally contained significant three-dimensional patterns in skin injuries or foodstuffs. The quality of these cases of precedent might not be representative of the majority which followed. There was, however, little science involved in the ultimate opinions dentists delivered in any of these cases. The appellate opinion in Marx realized this when bitemark admissibility was approved on the basis of the “trier of fact” (usually the jury) making their own determination from the evidence presented. Jury acceptance of bitemark testimony is no substitute for population studies and reliability testing. The “generally accepted” methods in use haven’t changed much and the glaring weakness is in the lack of pragmatic determination of “uniqueness” as seen in bitemarks on skin and inanimate objects. Hundreds of cases have occurred since the 1970’s and the issue of individuation has not been resolved scientifically. This place’s odontology at the bottom of the list of other forensic disciplines. Maybe Questioned Document Examination is worse off. There is no reliable way of saying, other than colloquially, that one or more tooth marks seen in a wound are conclusively unique to just one person in the population. Because of this vacuum, value judgements abound in our discipline. Proffering the testifying expert’s years of experience is a popular means of “proving” uniqueness.” He or she has seen more bitemarks. This misses the scientific point and is misleading to a lay jury that is given the responsibility of filtering good science from bad. The confidence level of expert testimony must be based on data available to BOTH the dentist and the court. This scientific data does not exist. Until this changes, the admissibility of bitemark analysis should be limited to a “possible” determination. The odontologist doesn’t have a basis to expand an opinion beyond that. Marks in skin can be spatially associated to the edges of teeth by trained dentists. That is within the realm of physical comparison methodology. The “unique” or “reasonable dental certainty” description currently used to characterize a positive match are not supported by anything other than personal opinion. That is the reason for this proposed limitation on bitemark testimony.
There have been and will continue to be cases where the defendant’s teeth and an unknown bite pattern shows a common pattern and shape. The determination of common similarities equaling a finding of uniqueness can’t be made on such general features. The equation using values of 1 to 4 (one being common) for these generic features such as arch width and tooth width should not be 1x1x1x1=4. The Milone(3) case and its derivative commentaries(4),(5) should be read by everyone to underscore this limitation.
I also propose that a bifurcation must take place in possible value of different types of bitemarks. A three dimensional bite, as in Marx (on a nose), allows for much more accuracy in the “wound to teeth” comparison. Questions of spatial relationships are substantially answered and discrepancies leading to subjective visualization are minimized. The answer is demonstrable and the commonly used syllogism of “its much like a toolmark” is applicable. A two-dimensional wound is a separate and much greater challenge. These cases lack “toolmark” clarity and are the foundation for uncontrolled opinion and poor sensitivity and specificity in analysis.
Research must progress to raise the current anecdotal level of individuation in contemporary bitemark analysis. A concerted effort to find funding and research facilities has to be done by this organization. It will be the cheapest assurance that our future in court will be positive, rather than controversial. After the research is done, the “possible”might then become “unique.”
1. Doyle v. State, 159 Tex. C.R.310, 263 S.W.2d 779 (Jan 20, 1954)
2. People v. Marx, 54 Cal.App3d 100, 126 Cal.Rptr. 350 (Dec. 29, 1975)
3. People v. Milone, 43 Ill.App.3d 385, 356 N.E.2d 1350 (Nov. 12, 1976)
4. U.S. ex rel. Milone v. Camp, Slip opinion (U.S. Dist. Court, N.D.IL; Sept 29, 1992)
5. Milone v. Camp, 22 F.3d 693 (7th Cir.) (Apr. 21, 1994)
About the Author: C.Michael Bowers provides expert and criminal litigation support in matters pertaining to forensic dentistry and DNA profiling. Originally published at Vol. 4, No. 2, December 1996; American Board of Forensic Odontology Newsletter.
From the Innocence Project http://www.innocenceproject.org/
Forensic science errors are a leading cause of wrongful convictions nationwide. Scientific errors, fraud or limitations were a factor in 63% of the first 86 DNA exoneration cases, according to an August 2005 analysis of the cases published in Science magazine. These forensic science mishaps include everything from lab analysts who committed fraud to expert witnesses who relied on analyses of forensic disciplines which have never been adequately validated to identify a perpetrator such as: hair, bullets, handwriting, footprints, or bite marks. Using DNA – which provides a precise identification that other methods cannot – wrongful convictions were exposed years or even decades later.
Bite mark analysis is particularly troubling because of the almost complete absence of validated rules, regulations, or processes for accreditation that establish standards for experts or the testimony they provide. Unlike other areas of forensic analysis, forensic dentists are generally self-employed rather than employees of an accredited lab and hence they can avoid even that layer of oversight. Moreover, no government entity has ever reviewed the validity of bite mark evidence. “[B]ite mark analysis has never passed through the rigorous scientific examination that is common to most normal sciences,” according to the 2002 book Modern Scientific Evidence: The Law and Science of Expert Testimony.
There are approximately 100 forensic odontologists in the country who have been certified by boards controlled by other odontologists – generally speaking, their friends and colleagues – but not accredited by an entity that applies scientific rigor. Much forensic odontology work involves comparing dental records to well-preserved teeth of people who died in fires or other tragedies – but comparing an accused person’s teeth to marks on a victim’s body is far more subjective, and far more prone to error. As noted in Modern Scientific Evidence, “The rate of error in bite mark identification, particularly the rate of false positive errors, appears to be quite high.” In fact, only three studies have examined the reliability of bite mark analysis. All three show serious problems. One showed an error rate – a rate of false identifications – as high as 91%. Another (conducted by the American Board of Forensic Odontology) found a 63.5% rate of false identifications, and the third showed an error rate of 11.9% to 22% of false identifications among forensic odontologists and noted that the “poor performance” is cause for concern because it has “very serious implications for the accused, the discipline, and society.”
The Innocence Project believes that all forensic disciplines need to be scientifically validated through truly independent research and peer review before the methodologies are used in criminal cases where life and liberty are at stake. Moreover, even if the methodology is valid, bias, incompetence, or a lack of adequate internal controls can compromise the integrity of the results. The Innocence Project’s position is based on fundamental principles of good science and the disturbing narratives of innocent people, arrested and convicted of crimes based on bite mark analysis, only to eventually be proven innocent through DNA testing.
Following are five cases where people were convicted based largely on bite mark analysis, only to be proven innocent through DNA years later:
Willie Jackson in Louisiana
DNA testing exonerated Willie Jackson in 2006 and implicated his brother in a Louisiana rape. The victim identified Jackson as the assailant in a photo array and also in a live line-up. His brother also appeared in a line-up but was not identified by the victim. However, Jackson lived 185 miles away from the scene of the crime, while his brother lived in the area. Several other factors tied his brother to the crime: When police searched Jackson’s mother’s house, they found a sweater with his brother’s name on it that was similar to the one described by the victim; Jackson’s mother drove a car similar to the victim’s description; and a bartender testified that he saw Jackson’s brother, and not Jackson himself, in the same bar as the victim the night of the rape. In addition to eyewitness testimony, the prosecution presented a forensic odontologist who testified that bite marks on the victim matched Jackson’s teeth. Just days after Jackson was convicted in 1989, his brother confessed to the crime but was not charged. Sixteen years later, Jackson was released based on DNA test results. In addition, a second, independent odontologist argued that the earlier finding was incorrect and that the bite marks actually matched Jackson’s brother. His brother was already serving a life sentence for an unrelated rape.
Ray Krone in Arizona
Based largely on bite mark analysis, Ray Krone was convicted of murdering a Phoenix bartender and sentenced to death plus 21 years. Krone became known as the “snaggle-tooth killer” when an impression of his jagged teeth (in a Styrofoam cup) was said to match the bite marks on the breast and neck of the murder victim. She had been fatally stabbed, and the perpetrator left behind little physical evidence. There were no fingerprints; blood at the scene matched the victim’s type; and saliva on her body came from someone with the most common blood type. There was no semen, and no DNA tests were performed. First convicted in 1992, Krone won a re-trial in 1996 and was convicted again mainly on the state’s supposed expert bite-mark testimony. His death sentence, however, was reduced to life in prison. Finally, in 2002, Krone was released after DNA testing proved that he could not have been the perpetrator. Instead, saliva and blood found on the victim matched a convicted rapist.
Calvin Washington in Texas
Calvin Washington was convicted of murder and sentenced to life in prison in Texas in 1987. It was alleged that Washington, either acting alone or with Joe Sidney Williams, robbed, raped, and murdered the victim. An expert witness testified that bruises on the victim’s body were bite marks that matched Williams’ teeth. A jailhouse informant claimed that he heard Washington and Williams make incriminating statements when he walked by their hotel room one night. Meanwhile, the defense presented over a dozen Waco, Texas, police officers who testified to the unreliability of the jailhouse informant. The prosecution also produced evidence that the defendants were in possession of the victim’s car and had sold items belonging to the victim on the night of the crime. Both Williams and Washington were convicted. Williams’ conviction was overturned and the prosecution declined to retry him. Washington served 13 years in prison before DNA test results exonerated him in 2001. Testing also showed that fluids taken from the victim did not come from Washington, but rather from another man, since deceased.
James O’Donnell in New York
James O’Donnell became a suspect in an attempted sodomy case on the basis of a police sketch. A Staten Island resident, having seen the sketch in the newspaper, contacted the police and named O’Donnell. The victim later identified O’Donnell in a photo array and in a live line-up, but a second witness who was also at the scene of the crime did not identify him. The victim had passed out after struggling with the assailant. He bit her on the hand and she scratched him. The bite mark was said to match impressions of O’Donnell’s teeth, but DNA testing of the saliva on the bite mark later disproved the finding. Testing of the fingernail scrapings matched the saliva and further proved that O’Donnell was not the perpetrator. He was exonerated in 2000, after over two years of wrongful incarceration.
Dan Young in Illinois
Dan Young spent 12 years in prison before DNA testing cleared his name in a Chicago murder. His conviction was based on a bite mark match and a false confession. Young was mentally handicapped and could not read or write. An initial analysis of the bite mark found a match between Young’s teeth and the bite mark, but a more recent analysis, commissioned by the defense, contradicted this finding. The odontologist who aided in Young’s conviction later said that the prosecution pushed him to exaggerate his results. Young was released in early 2005.
Bite mark analysis has also caused an unknown number of innocent men and women to be arrested and charged with crimes they did not commit. Some of these people became ensnared in police investigations on the basis of nothing more than an erroneous bite mark “match.” The following people languished in jails awaiting trial until DNA testing lead to their release:
- In 1994, Anthony Otero of Detroit was charged with first-degree murder, rape, and larceny in the death of a 60-year-old woman. A forensic odontologist testified at a preliminary examination that Otero was “the only person in the world” who could have inflicted bite marks found on the victim’s breast and thigh. After Otero spent five months in jail awaiting trial, the state dismissed the charges after a newly available DNA test excluded him as the perpetrator.
- Dale Morris, Jr., was arrested in 1997 based on bite mark analysis matching his dentition to a mark on a nine-year-old murder victim. Morris was a neighbor to the little girl who was found stabbed, sexually assaulted, and bitten in a field near her Florida home. He spent four months in jail until DNA tests proved his innocence.
- A police dog led officers to the home of Edmund Burke during an investigation in the murder of a 75-year-old woman from Massachusetts. The assailant had left a bite mark on her breast. The odontologist in the case compared photos of the bite wound with a mold made from Burke’s teeth and concluded “to a reasonable scientific certainty” that Burke had made the mark. However, just weeks after his arrest, DNA taken from saliva from the bite mark was tested and Burke was released.