Attorneys for a condemned Missouri inmate warn that the state is preparing to execute a potentially innocent man.
Williams' exoneration, should it come, now rests in the hands of the U.S. Supreme Court and newly elected Missouri governor, Eric Greitens, a Republican.
The US Supreme Court has not yet ruled on the motion.
In a statement issued Monday, the state attorney general's office said Williams' guilt was proven without DNA evidence.
"These scratches would leave DNA traces on the victim, but Williams' DNA was not found underneath the victim's fingernails, just like it was someone else's DNA that was found on the murder weapon", Gipson told Al-Jazeera.
"There is evidence that has not been considered by a court", Chapel said, according to Missourinet.
His team says that DNA found on the knife during testing this December could not be the convicted killer, but matched another unidentified man.
"There is no physical evidence, no eyewitnesses that directly connect Williams to the murder, the DNA on the weapon wasn't his, the bloody footprint at the murder scene wasn't from Williams' shoe and was a different size, and the hair fibers found weren't his", Gipson told Al-Jazeera.
But state prosecutors contend there is enough other evidence to assure Williams' guilt, including the victim's personal items recovered from the condemned man's vehicle.
The case hinged on the testimony of two other criminals, Williams' former girlfriend and the cell mate he bunked with while serving time for an unrelated crime.
The non-DNA evidence includes a laptop belonging to the victim's husband, which Williams sold and police recovered, and some of the victim's personal items, which police found in the trunk of the vehicle Williams drove, according to court documents.
Williams has been convicted of killing Lisha Gayle while burglarizing her home in a gated University City community. The St. Louis County case is gaining global attention.
Williams was also tied to stolen items from Gayle's home.
Prosecutors dismissed the DNA evidence, saying "it would be unsurprising" that other people's DNA would be on the kitchen knife used for the murder. "Whatever one's views of capital punishment, it is both morally and constitutionally intolerable for a death sentence to be imposed if the defendant is innocent or if the verdict is marred by racial discrimination".