Can science help bring justice to those charged with arson?
The typical local arson investigator, assigned from the police force or the fire department, has never taken college-level chemistry or physics. He learned on the job, by watching other arson investigators, many of whom have learned the trade from their superiors. The misguided notions that older arson investigators subscribed to seemed commonsensical, if you didn’t insist on seeing lab work to support them. Year after year, poorly trained police or fire department officials contributed to faulty convictions.
A lot of bad science has been applied to arson investigation,” says John Lentini, a renowned fire expert who has given exculpatory testimony in at least 40 arson cases since 2000. His most recent case, now under review, involves a Massachusetts man convicted of arson by Molotov cocktail, even though not a single glass fragment from the supposed bottle bomb was found at the scene.
“I shudder to think how many wrongful convictions there are,” says Richard Roby, president and technical director of Combustion Science and Engineering, a fire-
protection engineering firm based in Columbia, Maryland. Roby has testified for several men charged with arson. One, named Michael Ledford, could not have been
at the scene when the fire that killed his son was allegedly set, according to Roby’s calculations, yet he is now serving a 50-year sentence. “It’s amazing to think how long it takes for basic science to be accepted,” Roby says. “I lose sleep over this every week.”
Scientists continue to discover new fire clues. At several labs, investigators are examining the burn patterns resulting after they pour a range of flammable liquids on floor surfaces, including vinyl, wood, carpet, and concrete, and set them ablaze. In some cases, they have found, a flammable liquid actually protects a floor from bursting into flames because the liquid shields it from radiant heat. At Hughes Associates, a Baltimore-based fire science and engineering firm, senior engineer Dan Gottuk was struck by one experiment in which he compared burn patterns left by a liquid-fueled fire to those left by a melting polyurethane couch. “We showed that in many situations you really can’t tell the difference,” he says.
http://discovermagazine.com/2011/nov/12-spark-truth-science-bring-justice-arson-trials
Seven Myths About Arson:
http://discovermagazine.com/2011/nov/24-seven-myths-about-arson