It has been more than 30 years since a Dallas County jury convicted Steven Chaney of capital murder on the strength of a bite mark.
“I wouldn’t ask you to convict just based on the testimony of the tennis shoes, of the statements made to Westphalen, or the statements he made to Curtis Hilton,” a prosecutor said during his closing arguments. “But, by golly, I’m going to ask you to convict on that dental testimony.”
Wednesday morning, after spending 28 years in prison in relation to a double homicide, Chaney was ruled innocent by the Texas Court of Criminal Appeals. He’s been out of prison since 2015, released on bond after his conviction was overturned.
At the root of the exoneration: new science delegitimizing dental testimony, wherein an expert had proclaimed just one in a million odds that the bite mark on a victim’s arm hadn’t come from Chaney. In agreeing with the habeas court, the state appeals court concluded not only that new science would’ve prompted a different interpretation of the bite mark today, but that an expert witness falsely testified at trial that the bite occurred at the time of the murder—as opposed to his initial read that the mark was two or three days old.
The incident in question occurred on June 20, 1987, inside a Dallas apartment, where two friends discovered the bodies of John and Sally Sweek, who’d each been stabbed multiple times and had their throats slashed.
During the investigation, police discovered bloody shoe prints and a few dozen fingerprints—including a single partial thumbprint belonging to Chaney. Although some of the prints were bloody or near blood, Chaney’s was not.
The Sweeks were drug dealers, and at trial the state theorized that Chaney was an addict who killed the couple because of an outstanding debt, and to get more cocaine. It argued that Chaney’s response when an investigator (John Westphalen) approached him about the murder—which had been to immediately provide nine witnesses as alibis—showed consciousness of guilt. In the state’s telling, the motive came from the testimony of a Chaney-acquaintance (Curtis Hilton) who said Chaney was persistent about the money he felt Hilton owed him, and about his desire for more drugs. Prosecutors also drew a comparison between the shoe prints and a pair of sneakers Chaney wore during questioning, which were subsequently confiscated as evidence.
But the defense batted away the shoe claims with a Foot Locker manager who said the sole identified in the prints were in 50 to 80 percent of the athletic shoes made in the last 15 years. And it played up the nine witnesses who accounted for Chaney’s whereabouts the day of the murder.
It was the dental testimony that was damning. A pair of forensic odontologists pegged the mark on John Sweek’s arm as a bite from a human. One expert, Dr. James Hales, called it a “perfect match” with “no discrepancies,” the basis of his claim that there was only a one in a million chance that it could belong to someone else. Dr. Homer Campbell, the other expert, chimed in that he could say to a “reasonable degree of dental certainty” that the mark was from Chaney.
But in granting Chaney relief, the CCA wrote that new “peer-reviewed studies discredit nearly all the testimony given by Hales and Campbell about the mark on John’s left forearm and Chaney being a ‘match.’”
The State’s case would have been incredibly weakened had Chaney’s newly available scientific evidence been presented at his trial. Instead of supporting the conclusions that Chaney bit John at the time of the murders, the evidence would now show, at most, only that John might have been bitten two to three days before the murders and that if John was bitten by someone, that person could be Chaney (or anyone else on the planet whose dentition has not been excluded).
The court found the rest of the evidence weak, agreed that the prosecution had suppressed evidence in its pursuit of a conviction, and tacked on its agreement that Hales’ one-in-a-million claim constituted false testimony. Hales confessed that he knew the body of science at the time did not support that testimony, and notes later discovered in his trial file showed that he’d initially written down “thousands to one,” with a nearby note of “100,000 to 1.”
But the most undeniable pieces of evidence supporting innocence are laid out in the appeals court’s consideration of Chaney’s actual-innocence claim. That’s where the court dives into, among other things, DNA results from the scene:
While not completely exonerating, new post-conviction DNA results of all the available crime-scene evidence excluded Chaney as a contributor from every item tested. At least three male DNA profiles were discovered on or under Sally’s fingernails, but Chaney was not one of the contributors. Also, Chaney was excluded as the source of hairs found in Sally’s right hand.
The DNA was tested as a part of an investigation by Dallas County’s Conviction Integrity Unit, the corner of the DA’s office tasked with examining possible wrongful convictions. It worked alongside the Innocence Project. During the course of the investigation—which was handled by CIU prosecutors Patricia Cummings and Cynthia Garza, working under former District Attorney Susan Hawk—witnesses led the unit to renew an original investigative theory that the two were murdered by individuals with ties to a cartel. Two new suspects were identified, “whom the habeas court found likely murdered John and Sally because of outstanding drug debts.”
In deeming Chaney innocent, the court paired the new lead with the updated science and false evidence, flashing a light on how those items could impact a jury’s interpretation of the rest of the evidence. The habeas court had concluded, and the appeals court agreed, that the reliability of the nine alibi witnesses looks much different without scientific evidence that at the time seemed to prove Chaney brutally assaulted John with his teeth.
The exoneration comes amid renewed hope that Dallas County’s Conviction Integrity Unit, which examines possible wrongful convictions, could regain some of the fervor under DA-elect John Creuzot that it once had under former DA Craig Watkins, who launched the unit. Wednesday marks the sixth exoneration since Watkins left office in 2015. His CIU, the first in the country, freed 31 people over his eight years in office. Representatives with the Innocence Project could not be reached for comment.