Science casts cloud over arson convictions

A major revelation came from greater understanding of a phenomenon known as “flashover.” When a fire burns inside a structure, it sends heat and gases to the ceiling until it reaches a certain temperature — and then in a critical transition, everything combustible in that space will catch fire. Instead of a fire in a room, now there is a room on fire.

When that happens, it can leave any number of signs that investigators earlier thought meant arson — like the burn holes on the floor that used to prove multiple starting points. And it can cause a fire to burn down from the ceiling — not up.

Significantly, flashover can create very hot and very fast-moving fires. And it can occur within just a few minutes, dashing the concept that only arson fires fueled by accelerants can quickly rage out of control.

The studies began to chip away at the old beliefs, but it took years. Through the 1980s, texts at the National Fire Academy in Emmitsburg, Md., still taught the traditional techniques.

It wasn’t until 1992 that a guide by the National Fire Protection Association — “NFPA921: Guide for Fire and Explosion Investigations” — clearly laid out, in a document relied upon by authorities nationwide, that the earlier beliefs were wrong.

“It’s not that they’re bad investigators or there’s been any conspiracy to promulgate erroneous conclusions — it’s just the way it was,” says Custer, the former associate director of the national Fire Research Laboratory and one of the principal editors of the 1992 guide.

“How many years did we think the Earth was flat?”

Suspicious investigators
In the hours before daybreak on July 29, 1989, police and firefighters quickly became suspicious.

Han Tak Lee seemed calm. He didn’t cry. He sat on a bench across from the burning cabin with two bags of luggage at his feet.

State Trooper Thomas Jones, doubling as county fire marshal, wrote in his report a week later: “Mr. LEE remained almost emotionless and while in view of this officer made no attempts to console his wife (when she arrived from New York later that day). Mrs. LEE on the other hand was being escorted to the scene and upon nearing the burnt building almost collapsed and had to be physically assisted from the scene.”

Prosecutor E. David Christine Jr. argued Lee’s demeanor was that of a killer, not a grieving father.

But Koreans say that men traditionally don’t express much emotion, and never in public. And Lee is nothing if not traditional, his wife and surviving daughter say.

Lee says now that, watching the cabin burn, he was overwhelmed and stunned into silence.

“I found that I just lost my spirit and my mind there. It felt like all the blood drained out of my body,” he says. “In Korea, men are not allowed to cry. If your daughter is suddenly found dead, there’s nothing you can do. You just lost your soul. You can’t even think.”

MORE FROM SCIENCE

Science Section Front

Cosmic Log: The bird vs. the Big Bang Machine Future of evolution: What will we become? Good news! NASA says world won’t end in 2012 Top 10 doomsday predictions that failed Friday the 13th: Your luck is about to change Humans still evolving as our brains shrink India to move all zoo elephants to wildlife parks Super-sniffing bees combat colony pest Power cut during heat wave shuts Australian zoo Record high temps are double the lows Science Section Front   Add Science headlines to your news reader: