Juan Melendez, 50, was condemned for the murder of Delbert Baker in Polk County.

The murder conviction and death sentence were upheld several times. The latest appeal was filed last fall and a hearing was this summer.

In Wednesday's ruling, Circuit Judge Barbara Fleischer noted that there was no physical evidence against Melendez and that jurors did not get to hear important facts about the state's two witnesses, which might have discredited their testimony.

The evidence that prosecutors withheld from Melendez's trial attorney "seriously undermines the credibility of the two key state witnesses," Fleischer wrote.

The jury also did not hear testimony from several other witnesses that a man by the name of Vernon James told them he had killed Baker, Fleischer wrote.

"The evidence also helps to substantiate the defense theory that someone other than the defendant committed the homicide," she wrote, noting that police didn't prepare their reports until six months after the investigation.

That delay, she wrote, "provides an opportunity to question law enforcement regarding its methods, procedures, and motives in conducting its investigation."

When everything is added up, confidence in Melendez's sentence and conviction is undermined, she wrote.

"Without knowledge of and access to the suppressed evidence, the defendant did not receive a fair trial," the judge wrote.

Melendez's appeal attorney, Marty McClain of New York City, said James was killed a couple of years after Melendez was sent to death row.