For decades, the criminal justice system in the United States has convicted defendants on the basis of forensic evidence–some of which we now know to be highly suspect or “junk” science. But years after the National Academy of Sciences raised questions about hair strand, shoe print and bitemark analyses, and other forensic methodologies, courts are still admitting them as evidence.
Why is scientific evidence with a high rate of error making its way into court? The answer: trial judges, who act as “gatekeepers” and have the power to decide whether or not forensic evidence is admissible, are admitting them, according to an Albany Law Review study.
Judges typically adhere to precedent. Even though the National Academy of Sciences Report, issued in 2009, established that many of the once commonly accepted forensic tests were shown to “lack scientific validity or to be of only limited probative value,” courts are still admitting expert testimony on the basis of them.
“We know juries place great weight on scientific-sounding evidence, disregarding all other evidence to the contrary,” said the study’s authors, noting that post-conviction DNA testing and exonerations have long since cast doubt on such evidence.
The study, entitled “It’s Not a Match: Why the Law Can’t Let Go of Junk Science,” was authored by Aliza B. Kaplan of Lewis & Clark Law School, and Janis C. Puracal of the Oregon Innocence Project and Maloney Lauersdorf Reiner, PC.
The National Academy of Science (NAS) conclusions were strengthened by the subsequent President’s Council of Advisors on Science and Technology (“PCAST”) Report, issued in 2016. They reviewed whether forensic evidence, such as DNA testing and bite mark analysis, are supported by reproducible research and, thus, reliable.
Both concluded that a great deal of forensic evidence is insufficiently tested for validity and reliability. The NAS Report, for instance, claims that “[m]uch forensic evidence—including, for example, bite marks and firearm and toolmark identifications—is introduced in criminal trials without any meaningful scientific validation, determination of error rates, or reliability testing to explain the limits of the discipline.”
Of the decisions reported since the release of the NAS Report in 2009, 97 cases mentioned the NAS Report , but just ten decided to challenge forensic evidence or to agree post-conviction that the evidence should’ve been excluded. Since the release of the PCAST Report, seven cases mention PCAST and most of those courts chose to admit questionable forensic evidence over the objections of the defendant.
A forthcoming study, “Forenisic Bitemark Identification Evidence in Canada,” found that the Canadian Supreme Court has repeatedly directed trial judges in that country to exercise a robust gatekeeper role when faced with requests for admission of invalid science. But none of the courts excluded bite mark analysis, nor questioned the scientific validity of the practice.
The study also found that there were “14 cases in which courts relied on a forensic bitemark identification, a number that likely underestimates the use of this practice.”
“Still,” the reported added, “in the cases we found, forensic bitemark experts overstated the accuracy and reliability of their practice, and did not appear to disclose the considerable controversy in the field.”
That study was conducted by Jason Chin of The University of Queensland – T.C. Beirne School of Law, and D’Arcy White of the University of Toronto, Faculty of Law.
Today, the Federal Rules of Evidence (FRE) 702 guides decision-making on admissibility of scientific evidence. It declares that a trial court consider “whether the expert is proposing to testify to (1) scientific knowledge that (2) will assist the trier of fact to understand or determine a fact in issue,” in deciding to admit evidence and testimony. The admissibility of scientific evidence in trial court is determined by the judge.
And judges remain the principle obstacles.
The Supreme Court of Utah has noted that lawyers and judges “tend to comfortably rely upon settled legal precedent and practice, especially when long-settled technical rules are concerned, and to largely ignore the teachings of other disciplines, especially when they contradict long-accepted legal notions.”
Nevertheless, chances of reform coming from the federal government are slim. Following the release of the PCAST report, no plan for change was implemented by the Obama administration. In April 2017, the Department of Justice announced it wouldn’t be renewing the National Commission on Forensic Science.
Attorney Generals Loretta Lynch and Jeff Sessions have both expressed confidence in the status quo, the Albany study noted.
Individual states, however, have made strides in improving how the courts handle forensic evidence. The Texas legislature blazed a trail by establishing the Texas Forensic Science Commission. The intention of the Texas Commission is to “investigate complaints involving forensic disciplines,” to “establish procedures, policies, and practices to improve the quality of forensic analyses conducted in Texas,” and “to establish licensing programs for forensic disciplines.”
The Texas Forensic Science Commission comprises seven independent scientists and two attorneys, a prosecutor and a defense lawyer, who are unpaid and make nonbinding recommendations on forensic matters. The Texas Commission can hear from experts in an area, review studies, and collaborate with professionals in the justice system to improve education and training in forensic science and the law.
The solution proposed by the study is the creation of a “state-specific forensic resource counsel,” something that already exists in North Carolina. The job of North Carolina’s forensic resource counsel is “to assist North Carolina public defenders and private appointed counsel in understanding and if appropriate, challenging the forensic science evidence in their cases.”
In order to establish a conversation between the law and science, a forensic resource counsel would be responsible for “assembling commissions to review forensics within the state, proposing and appearing as amicus in hearings before Special Masters to explore advances in forensic methodologies and necessary changes in the law; collaborating with forensic resource counsel, lawyers, and experts in other states to find independent scientists who can further the research and assist with facilitated conversations with prosecutors, defense counsel, and judges; and offering seminar trainings for prosecutors, defense counsel, and the judiciary.”
The rigor and precision of forensic sciences is generally accepted by the public, but in the light of new evidence, a slow-to-change legal system will continue to potentially ruin lives unnecessarily.
The full study of, “It’s Not a Match: Why the Law Can’t Let Go of Junk Science”, can be found here.
The full study of, “Forensic Bitemark Identification Evidence in Canada,” is available here.
John Ramsey is a TCR news intern. Readers’ comments are welcome.