At the Marshall Project website, it's titled, "The Prosecutor and the Snitch."
Here's the beginning of this must-read:
For more than 20 years, the prosecutor who convicted Cameron Todd Willingham of murdering his three young daughters has insisted that the authorities made no deals to secure the testimony of the jailhouse informer who told jurors that Willingham confessed the crime to him.
Since Willingham was executed in 2004, officials have continued to defend the account of the informer, Johnny E. Webb, even as a series of scientific experts have discredited the forensic evidence that Willingham might have deliberately set the house fire in which his toddlers were killed.
But now new evidence has revived questions about Willingham’s guilt: In taped interviews, Webb, who has previously both recanted and affirmed his testimony, gives his first detailed account of how he lied on the witness stand in return for efforts by the former prosecutor, John H. Jackson, to reduce Webb’s prison sentence for robbery and to arrange thousands of dollars in support from a wealthy Corsicana rancher. Newly uncovered letters and court files show that Jackson worked diligently to intercede for Webb after his testimony and to coordinate with the rancher, Charles S. Pearce Jr., to keep the mercurial informer in line.
Earlier coverage of Todd Willingham's case begins at the link.
While he was a reporter at the Chicago Tribune, Possley and Steve Mills first reported on the Willingham case in a 2004 Chicago Tribune series on junk science. The December 9, 2004 report was titled,"Man executed on disproved forensics."
All related coverage is in the Todd Willingham category index.
The Innocence Project has a Todd Willingham resource page which provides a concise overview of the Willingham case with links to all relevant documents.