It's Halloween. So what could be scarier than a state throwing a person in prison for arson when the fire was accidental?

Executing him.

That's the lesson of a report released Friday by the Texas Forensic Science Commission. The report is the latest twist in an ongoing legal saga following Texas's 2004 execution of Cameron Todd Willingham. In 2004, before Texas executed Willingham for the alleged arson murder of his three children, the Texas Board of Pardons and Parole had received a report by a renowned fire scientist named Dr. Gerald Hurst. Dr. Hurst's report showed that the "fire-science" testimony accusing Willingham of arson at his trial was farcical and anything but scientific. Governor Rick Perry received the report too. Willingham's execution went forward despite that the debunked "fire science" had been the centerpiece of the state's case against him.

Concerned Texas legislators created a Forensic Science Commission, which took up Willingham's case in 2008. After shenanigans by Governor Perry threatened to derail the Commission's work and related wrangling that has gone on for three years, the Commission released findings in April showing that the "science" behind Willingham's conviction and death was not science at all, and could be more accurately described as a collection of wives' tales.

On Friday, the Commission supplemented its report, finding that it had no jurisdiction (under the statute creating it) to determine if the faulty science used at Willingham's trial was the result of professional negligence or misconduct by fire investigators for the state.

But in a hopeful silver lining for people imprisoned for arson in Texas, the report included a commitment from the state fire marshal's office, which will partner with the Innocence Project of Texas, to identify and reinvestigate old arson cases that may have been built on the same faulty "fire science" that spelled Willingham's demise.

The Commission's chairman, Dr. Nizam Peerwani, said "it is important to understand that science is an ever-changing process."

Dr. Peerwani is right. Even assuming that the state's experts are never negligent, and that police and prosecutors never commit misconduct, science is ever changing. What was true yesterday may be found false tomorrow.

Still, scientific testimony has its place. It may sometimes be a proper basis for convicting and imprisoning a person. If we find out it was wrong, we can always let the person out and try to repair the damage — as Texas will now attempt for victims of junk fire science.

But while science can be probed to reveal flaws in our past understanding of it, it can never bring back the dead. That's the frightening agony known by the family of Cameron Todd Willingham. And one we should thoughtfully consider before Texas or any other state executes again.

CORRECTION: The Texas Forensic Science Commission report was released on Friday, October 28, not Monday, October 31.

Learn more about the death penalty: Sign up for breaking news alerts, follow us on Twitter, and like us on Facebook.