Did Texas execute an innocent man?

FRONTLINE asked the question a year ago when we first aired Death by Fire, which rebroadcasts tonight (check local listings). The film examines whether Cameron Todd Willingham deliberately set a 1991 house fire that killed his three daughters. Willingham was executed for the crime in 2004.

But the question has reverberated over the past year, as Texas Gov. Rick Perry seeks the GOP nomination for president. Perry has defended the execution, describing Willingham as a “monster,” and saying in a GOP debate that he’s never struggled with the thought that an innocent person has been executed during his time in office.

At the heart of the debate over Willingham’s guilt is fire science: “A fire does not lie,” wrote the Texas investigators who originally determined the blaze was a classic case of arson. But more than a decade later, fire scientist Gerald Hurst reviewed the evidence and found that the fire could not have been purposefully set. “One might well wonder how anyone could make so many critical errors in interpreting the evidence,” he wrote questioning the original investigation.

Recent developments make it unlikely that we’ll ever get a definitive ruling on Willingham’s guilt or innocence. The Texas Forensic Science Commission [TFSC] was charged with evaluating the case; it concluded in a draft report [PDF] that the evidence used to convict Willingham was problematic. But shortly afterward, the Texas state attorney general ruled that the TFSC did not have the jurisdiction to examine the case. After the attorney general’s ruling, the commission did not feel it could move forward with a definitive finding of wrongdoing.

At the same time, the TFSC reached an agreement with the state fire marshal’s office to review other past cases. But critics say that any review involving current state fire marshal Paul Maldonato might be problematic because he stands by the original findings in the Willingham case.

Differences over arson investigations aren’t uncommon. John Lentini, a leading fire scientist, told FRONTLINE that “the fire investigation community largely consists of people who are firemen. They’re not scientists. They don’t have any formal scientific training. Extinguishing a fire and investigating a fire involve two different skill sets and two different mindsets.”

For more on this divide, and on how fire scientists are trying to better understand arson, take a look at this recent Discover Magazine feature. It traces the field’s history, explains some of the more recent developments in what we know about how things burn, and highlights what’s lacking around the country. In particular:

Most states have no legal requirements for a person to become a fire investigator, although they prefer him or her to take in-person or online training courses and pass rudimentary tests. In some states … a private investigator’s license is enough to give you legal authority to investigate a fire and testify about its origins. In other words, someone who makes his living spying on his clients’ spouses in hotel rooms can become an expert in fire analysis after an optional training period of just a couple of weeks.

Update [Oct. 28, 2011]: The TFSC today released 17 recommendations for arson investigations; included is the rec that “all cases involving people locked up on arson convictions [in Texas] be reviewed.”

Dig Deeper: Read David Grann’s exceptional New Yorker feature on the case, “Trial by Fire,” and Michael Hall’s Texas Monthly story on Ernest Willis, who was sent to death row based on arson evidence almost identical to that in the Willingham case. The only difference? Willis was eventually exonerated.