Is there a constitutional right not to be convicted based on junk science? For years, the U.S. Supreme Court has failed to directly grapple with that question — so much so that Justice Sonia Sotomayor recently said that Congress and state legislatures should tackle the problem now instead of waiting on the courts to fix it.
On July 2, the court unanimously declined to review the case of Charles McCrory, who was convicted in Alabama in 1985 for the murder of his wife, based almost exclusively on bogus bite-mark testimony. Bite-mark analysis has been roundly discredited by scientists and, to date, is behind at least 39 wrongful convictions or indictments.
Bite-mark evidence is among a host of problematic, scientifically questionable forensic practices widely used in the criminal legal system. While a number of forensic practitioners have acknowledged the problem and sought to get their disciplines on firmer scientific footing, the law has not caught up. Ostensibly, courts are supposed to vet forensic evidence before trial, though because judges are not scientists — and most lack any science training — this is rarely effective, and they often allow even the most questionable science into evidence.
For people like McCrory subsequently convicted based on junk science, there is often no straightforward way for the courts to revisit or correct old cases based on outdated and debunked forensic practices. The law favors finality, so once someone is sent to prison, it becomes difficult to challenge a conviction based on junk science, and judges often deny appeals based on procedural matters without ever engaging with those flaws.
While the Supreme Court has occasionally acknowledged this problem, among her colleagues, Sotomayor was alone in calling out the crisis it has created. In a statement alongside the denial of McCrory’s appeal, Sotomayor described his case as a symptom of a broader problem.
“Hundreds if not thousands of innocent people may currently be incarcerated despite a modern consensus that the central piece of evidence at their trials lacked any scientific basis.”
“This petition raises difficult questions about the adequacy of current postconviction remedies to correct a conviction secured by what we now know was faulty science,” Sotomayor wrote. “Hundreds if not thousands of innocent people may currently be incarcerated despite a modern consensus that the central piece of evidence at their trials lacked any scientific basis.”
To date, a handful of states have created a direct avenue of appeal for defendants convicted based on junk or debunked science. Texas was first, and Sotomayor notes that the statute has been used to exonerate a man named Steven Mark Chaney, who was convicted on bogus bite-mark evidence. California has a similar statute, which was used to exonerate Bill Richards, also convicted on discredited bite-mark analysis.
“These statutes,” Sotomayor wrote, “create an efficient avenue for innocent people convicted based on forensic science that the scientific community has now largely repudiated.”
A Flimsy Piece of Evidence
Throughout the nearly four decades since his wife’s murder, McCrory has maintained his innocence. In 2022, The Intercept published a lengthy investigation into McCrory’s case, detailing the flaws in the state’s case against him. The case has since attracted additional attention and media coverage, highlighting the problem of junk forensic science.
Julie McCrory’s body was found inside her home in Andalusia, Alabama, on the morning of May 31, 1985. Her head was bashed in, and she’d been repeatedly stabbed in the chest. The couple’s young son Chad, then 3 years old, was found unharmed in his crib. Police quickly zeroed in on McCrory as their only suspect: He and Julie were separated, and McCrory had been having an affair. At trial, the theory seemed to be that he’d savagely murdered Julie to be free from her.
The police investigation was cursory at best. Detectives searched McCrory’s home and car and found nothing to connect him to the bloody crime. Meanwhile, they ignored some evidence altogether, including two bedroom windows that were found open, but which investigators failed to dust for fingerprints. Police also failed to consider an alternate suspect, a man who worked at an excavating company bordering the McCrorys’ backyard and who, just weeks after Julie’s murder, committed a home invasion rape of another local woman. He was convicted and sent to prison for that crime.
Ultimately, the state latched onto a single piece of physical evidence against McCrory: a pair of small indentations on the back of Julie’s right arm, which prosecutors concluded was a bite-mark made by McCrory’s allegedly distinctive dentition.
To sell this theory, the state employed famed forensic dentist Richard Souviron, a star prosecution witness in the recent and sensational trial of serial killer Ted Bundy. Although Souviron initially said he couldn’t definitively link the two marks on Julie’s arm to McCrory, at trial he was unequivocal that they did indeed match.
More than three decades later, Souviron recanted his testimony. He provided an affidavit to McCrory’s lawyers, Chris Fabricant of the Innocence Project and Mark Loudon-Brown of the Southern Center for Human Rights, who presented it at a 2021 evidentiary hearing in Andalusia. “As a forensic odontologist I no longer believe the individualized teeth marks comparison testimony I offered in his case was reliable or proper,” Souviron wrote. “I no longer believe, as I did at the time of trial, that there is a valid scientific basis for concluding that the injury found on the skin of the victim in this case, assuming that the injury is in fact teeth marks, could be ‘matched’ or otherwise connected to a specific individual, such as Mr. McCrory.”
Fabricant and Loudon-Brown also presented testimony from two leading forensic dentists who were once bite-mark true believers but now admitted that the discipline lacked any scientific underpinning and was not valid evidence. They agreed to testify for free, they told the court, because they felt they had a duty to correct the record. Dr. Cynthia Brzozowski, a veteran forensic dentist from New York, told the court that she felt an “ethical and civic responsibility” to testify in cases like McCrory’s.
In response, prosecutors presented no evidence and instead insisted that McCrory was guilty based on the same case presented at trial, including the bite mark — which they now termed “teeth marks” — implying that this was a separate and valid discipline. It is not. Regardless, prosecutor Grace Jeter argued that, even if Souviron had not testified for the state, jurors could have looked at the marks on Julie’s body and the dental molds taken from McCrory and decided for themselves that the wounds were caused by McCrory’s teeth. In other words, the jury would have been free to engage in its own expert-free junk science.
In the end, Covington County Circuit Court Judge Lex Short agreed with the state, denying McCrory’s request for a new trial. The Alabama Court of Criminal Appeals upheld his decision. When McCrory’s lawyers asked the court to reconsider — in part because one of the justices had previously defended McCrory’s conviction while working as a prosecutor — the court simply reissued its opinion, complete with a typo that appeared in the original, along with a note saying that the judge had now recused herself.
McCrory’s team then appealed to the Supreme Court, which last week denied review.
Photo: Eric Gay/AP
Legislatures Need Not Wait
In their petition to the high court, McCrory’s lawyers asked the justices to consider two questions: whether the right to due process precludes a judge from deliberating on the appeal of a case they’d previously worked on, and whether there is a “due process right not to be convicted based on forensic evidence later shown to be fundamentally unreliable.”
Sotomayor joined her colleagues in declining to review the case, writing separately to explain. “I vote to deny this petition because due process claims like McCrory’s have yet to percolate sufficiently through the federal courts,” she wrote. “Legislatures concerned with wrongful convictions based on faulty science, however, need not wait for this Court to address a constitutional remedy.”
She notes that the “wholesale reevaluation” of forensics began with a congressionally mandated review by the National Academy of Sciences, which in 2009 issued a landmark report calling out nearly all forensic practices as scientifically unsound. The report included harsh criticism of bite-mark evidence. In 2016, those concerns were reiterated in a bombshell report from the President’s Council of Advisors on Science and Technology, a body that provides nonbinding recommendations to the U.S. president. The advisory council noted that bite-mark analysis would never likely pass scientific muster. Since then, the National Institute of Standards and Technology has issued its own exhaustive report finding the same.
For all intents and purposes, bite-mark evidence is dead — except in many courts, including in Alabama, which refuse to consider its status when evaluating appeals such as McCrory’s. In part, the problem is that statutes outlining post-conviction procedures were written prior to scientific advancements and do not contemplate the evisceration of an entire field of practice, leaving countless defendants convicted on junk science without any meaningful avenue to challenge their convictions.
Alabama’s prosecutors argue, first, that courts approved the use of bite-mark evidence in the 1980s, and so, in theory, it remains legitimate. Second, they argue that McCrory should have raised this issue years ago — back in 2002, in fact, when his lawyers first found a Newsweek article that questioned bite-mark evidence. In other words, their argument isn’t necessarily that bite-mark evidence is good or even valid, but rather, that Alabama law still recognizes the discipline, and there’s nothing new in McCrory’s appeals that changes that. Souviron’s affidavit recanting his testimony is too little, too late.
But just because some people were questioning bite-mark evidence in the early 2000s doesn’t mean that the scientific consensus had changed by then. It had not. And as The Intercept has reported, the battle over bite-mark evidence and other forms of junk science, continues to this day.
This makes it difficult for people like McCrory who seek to challenge their convictions based on new evidence. “Because science evolves slowly rather than in conclusive bursts,” Sotomayor wrote, it is hard to pinpoint when the science has truly changed and thus, when the issue should be raised on appeal. “Unlike a murder weapon left in an abandoned warehouse, forensic science does not lie around waiting for sudden discovery.”
And when scientific evidence is debunked, it’s a unique and ground-shaking event that needs addressing. “Evidence that an entire mode of forensic analysis has no scientific basis, however, is of a different category from evidence that might call into question a witness’s credibility or motive to testify.”
“Sotomayor’s concurrence is the first time any Supreme Court Justice has recognized the appalling legacy of wrongful convictions attributable to the use of junk science in criminal cases.”
Sotomayor’s statement is a big deal, said Fabricant, who also wrote a book on junk forensic science. “Justice Sotomayor’s concurrence is the first time any Supreme Court Justice has recognized the appalling legacy of wrongful convictions attributable to the use of junk science in criminal cases, and the failure of lower courts to take remedial action to address these all too common miscarriages of justice.”
Fabricant and Loudon-Brown, McCrory’s other lawyer, have filed an appeal in federal district court raising the same concerns they brought to the Supreme Court. While Alabama is arguing that the appeal should be tossed out, Sotomayor seems to be nodding to the district court to give McCrory’s case a thorough vetting.
“We appreciate Justice Sotomayor recognizing that Charles McCrory was convicted based on bitemark evidence that science has condemned and that the expert who testified against him has recanted,” McCrory’s lawyers wrote in an email to The Intercept. “But today an innocent man remains in prison, where he has been for almost 40 years. We will continue to fight for Mr. McCrory in the federal courts and call upon the State of Alabama to rectify this injustice.”