Canisius College study: Bite-mark analysis can lead to false convictions

11 Jan

Erik Eckholm wrote in the New York Times article, Mississippi Death Row Case Faults Bite-Mark Forensics:

In one of the country’s first nationally televised criminal trials, of the smirking serial murderer Ted Bundy in Florida in 1979, jurors and viewers alike were transfixed as dental experts showed how Mr. Bundy’s crooked teeth resembled a bite on a 20-year-old victim.

Mr. Bundy was found guilty and the obscure field of “forensic dentistry” won a place in the public imagination.

Since then, expert testimony matching body wounds with the dentition of the accused has played a role in hundreds of murder and rape cases, sometimes helping to put defendants on death row.

But over this same period, mounting evidence has shown that matching body wounds to a suspect’s dentition is prone to bias and unreliable.

A disputed bite-mark identification is at the center of an appeal that was filed Monday with the Mississippi Supreme Court. Eddie Lee Howard Jr., 61, has been on death row for two decades for the murder and rape of an 84-year-old woman, convicted largely because of what many experts call a far-fetched match of his teeth to purported bite wounds, discerned only after the woman’s body had been buried and exhumed.

The identification was made by Dr. Michael West, a Mississippi dentist who was sought out by prosecutors across the country in the 1980s and 1990s but whose freewheeling methods “put a huge black eye on bite-mark evidence,” in the words of Dr. Richard Souviron, a Florida-based dental expert who helped identify Mr. Bundy in 1979, in an interview last week.

Since 2000, at least 17 people convicted of murder or rape based on “expert” bite matches have been exonerated and freed, usually because DNA tests showed they had been wrongfully accused, according to research by the Innocence Project in New York. Dr. West was the expert witness in two of those cases.

In six additional cases, one involving Dr. West and one involving Dr. Souviron, indictments and arrests linked to bite-mark identifications were dropped after new evidence showed that the matches were wrong….http://www.nytimes.com/2014/09/16/us/mississippi-death-row-appeal-highlights-shortcomings-of-bite-mark-identifications.html?_r=0

A Canisius College study throws further doubt on the legitimacy of Bite-mark analysis.

Science Daily reported in Bite-mark analysis can lead to false convictions, landmark research shows:

Forensic science is a vital crime-fighting tool in today’s criminal justice system. But it can also lead to false convictions, according to H. David Sheets, PhD. Landmark research by the Canisius College physics professor proves that bite-mark analysis is “far from an exact science.”

Bite-mark analysis compares the teeth of crime suspects to bite-mark patterns on victims. Historically, forensic odontologists (dentists who provide forensic dental identifications in criminal investigations and mass disasters) operate under two general guidelines when interpreting bite-mark evidence. First, that everyone’s dental impression is unique to the individual, “similar to fingerprints,” Sheets explains. Second, that human skin — the most common material on which a bite mark is inflicted — reliably records an individual’s dental impression.

Bite-mark analysis is widely accepted in criminal courts and often presented as key evidence in prosecutions. “People assume that it’s close to fingerprints in terms of accuracy,” Sheets says. “But the notions that a person’s dentition is unique or that the human skin can accurately record an individual’s bite mark have never been validated scientifically.”

Sheets and his colleagues, Mary A. Bush, DDS and Peter J. Bush, from the University at Buffalo (UB) School of Dental Medicine, sought to do just that.

Using a variety of dental impressions, they examined more than 1,000 human dentitions and studied hundreds of bite marks in cadaver skin. With the help of computer analysis and applied statistics, the team then worked to match its database of bite marks to the correct dental impressions.

“When the dental alignments were similar, it was difficult to distinguish exactly which set of teeth made which bites,” Sheets says. “That tells us that a single bite mark is not distinct enough to be linked to a specific individual. It can actually point to many different individuals.” This means that a false identification is possible, which can lead a police investigation away from the real perpetrator and toward an innocent individual.

The Canisius-UB studies are among the largest conducted on bite-mark analysis and the first to use human-skin models (rather than animal models, wax or Styrofoam). More notable is that its findings call into question criminal convictions that rested entirely on bite-mark evidence.

Since 2000, at least 25 people convicted on bite-mark evidence have been exonerated due to advances in DNA testing, according to the Innocence Project. The national organization, which works to free wrongfully convicted individuals, is now using the Canisius-UB studies to help build a case for having bite-mark evidence cast out of criminal proceedings.

“This is an example of where science can help prevent future wrongful convictions and perhaps even provide some social justice to those already convicted,” Sheets concludes….                                   http://www.sciencedaily.com/releases/2016/01/160108134949.htm

Citation:

Bite-mark analysis can lead to false convictions, landmark research shows

Date:         January 8, 2016

Source:     Canisius College

Summary:

Forensic science is a vital crime-fighting tool in today’s criminal justice system. But it can also lead to false convictions, according to an expert, whose study proves that bite-mark analysis is “far from an exact science.”

Here is the press release from Canisius College:

Landmark Research Shows Bite-Mark Analysis Can Lead to False Convictions

Findings call into question criminal convictions that rested entirely on bite-mark evidence.

Released: 8-Jan-2016 9:05 AM EST
Source Newsroom: Canisius College

Newswise — Forensic science is a vital crime-fighting tool in today’s criminal justice system. But it can also lead to false convictions, according to H. David Sheets, PhD. Landmark research by the Canisius College physics professor proves that bite-mark analysis is “far from an exact science.”

Bite-mark analysis compares the teeth of crime suspects to bite-mark patterns on victims. Historically, forensic odontologists (dentists who provide forensic dental identifications in criminal investigations and mass disasters) operate under two general guidelines when interpreting bite-mark evidence. First, that everyone’s dental impression is unique to the individual, “similar to fingerprints,” Sheets explains. Second, that human skin – the most common material on which a bite mark is inflicted – reliably records an individual’s dental impression.

Bite-mark analysis is widely accepted in criminal courts and often presented as key evidence in prosecutions. “People assume that it’s close to fingerprints in terms of accuracy,” Sheets says. “But the notions that a person’s dentition is unique or that the human skin can accurately record an individual’s bite mark have never been validated scientifically.”

Sheets and his colleagues, Mary A. Bush, DDS and Peter J. Bush, from the University at Buffalo (UB) School of Dental Medicine, sought to do just that.

Using a variety of dental impressions, they examined more than 1,000 human dentitions and studied hundreds of bite marks in cadaver skin. With the help of computer analysis and applied statistics, the team then worked to match its database of bite marks to the correct dental impressions.

“When the dental alignments were similar, it was difficult to distinguish exactly which set of teeth made which bites,” Sheets says. “That tells us that a single bite mark is not distinct enough to be linked to a specific individual. It can actually point to many different individuals.” This means that a false identification is possible, which can lead a police investigation away from the real perpetrator and toward an innocent individual.

The Canisius-UB studies are among the largest conducted on bite-mark analysis and the first to use human-skin models (rather than animal models, wax or Styrofoam). More notable is that its findings call into question criminal convictions that rested entirely on bite-mark evidence.

Since 2000, at least 25 people convicted on bite-mark evidence have been exonerated due to advances in DNA testing, according to the Innocence Project. The national organization, which works to free wrongfully convicted individuals, is now using the Canisius-UB studies to help build a case for having bite-mark evidence cast out of criminal proceedings.

“This is an example of where science can help prevent future wrongful convictions and perhaps even provide some social justice to those already convicted,” Sheets concludes.

In addition to Sheets’ research on bite-mark analysis, he is a member of the Expert Working Group on Human Factors in Handwriting Analysis. Appointed by the National Institute of Standards and Technology (NIST) and the National Institute of Justice (NIJ), which provide oversight to the federal forensic community, the Expert Working Group on Handwriting Analysis is one of several discipline-specific groups charged with identifying the human factors that affect the outcomes of forensic analyses and developing best practices, based on scientific research, that will reduce the likelihood of errors in the future.

Canisius College, a Jesuit, Catholic university, offers outstanding undergraduate, graduate and professional programs distinguished by transformative learning experiences that engage students in the classroom and beyond. We foster in our students a commitment to excellence, service and leadership in a global society.

Contacts

Office Phones
  • Canisius College
  • News office:
  • 2001 Main St.
  • Buffalo NY 14208
  • United States
  • Phone news office:
  • Phone main:
  • Fax news office: 716-888-2965

 

Name   Title/Beat

Email

Phone

Eileen Herbert

Public Relations Director

Joseph Peterson, Ira Sommers, Deborah Baskin, and Donald Johnson wrote in The Role and Impact of Forensic Evidence in the Criminal Justice Process:

Conclusions & Discussion

In spite of the increased attention paid to forensic evidence over the past decade, there is little published empirical data identifying the types of evidence routinely collected, and the extent to which this evidence is submitted to and examined in forensic crime laboratories. There is even less research that describes the role and impact of such evidence on criminal justice outcomes. While the current study shows that

forensic evidence can affect case processing decisions, it is not uniform across all crimes and all evidence types; the effects of evidence vary depending upon criminal offense, variety of forensic evidence, the criminal decision level, and other characteristics of the case. The current study attempted to fill this gap in knowledge by examining the role and impact of forensic evidence on five felony crimes across five jurisdictions….

https://www.ncjrs.gov/pdffiles1/nij/grants/231977.pdf

The Canisius College study is important because it examines whether one type of forensic evidence has the validity to be used to support convictions in criminal cases.

Resources:

Bite-mark Analysis                                                                                                                   http://science.howstuffworks.com/forensic-dentistry3.htm

It literally started with a witch hunt: A history of bite mark evidence                                           https://www.washingtonpost.com/news/the-watch/wp/2015/02/17/it-literally-started-with-a-witch-hunt-a-history-of-bite-mark-evidence/

Cases Where DNA Revealed that Bite Mark Analysis Led to Wrongful Arrests and Convictions                                                                                                                                 http://www.innocenceproject.org/news-events-exonerations/cases-where-dna-revealed-that-bite-mark-analysis-led-to-wrongful-arrests-and-convictions

Where information leads to Hope. © Dr. Wilda.com

Dr. Wilda says this about that ©

Blogs by Dr. Wilda:

COMMENTS FROM AN OLD FART©
http://drwildaoldfart.wordpress.com/

Dr. Wilda Reviews ©
http://drwildareviews.wordpress.com/

Dr. Wilda ©
https://drwilda.com/

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: