On the Bookshelf: Identifying the victims of September 11
The quest to identify those who were killed in the September 11 attacks on the World Trade Center was a massive undertaking. Robert Shaler, then director of forensic biology at the New York City Office of the Chief Medical Examiner, faced the challenge of his career in the wake of the tragedy—and yet, initially, he says, he "naively" underestimated the magnitude of the job he and his colleagues faced.
"I never stopped to consider how long the project would take, the effect it would have on my life and family and especially the emotional toll it would extract." The process took over three years, and Shaler suffered a heart attack. He retired earlier this year to direct the Forensic Science Program at Pennsylvania State University. Shaler chronicles the journey—as well as the science that made it possible—in Who They Were: Inside the World Trade Center DNA Story: The Unprecedented Effort to Identify the Missing.
So was this undertaking as overwhelming as it sounds?
This was something of great historical importance to the United States—you can well imagine with 2,700 people dead. We had, simply, huge numbers of samples [some 20,000] that had to be analyzed. There were people who had died together. So just collecting one sample wasn't enough. We had to sample the tissues around the bone, and the bone itself, to obtain multiple samples.
What don't people understand—or, perhaps, what is most difficult to explain—about using DNA to make identifications?
The DNA has to be good enough quality, and just because it's there, doesn't mean it's good quality. The DNA in the bodies was in pretty bad shape. These bones were exposed to extreme temperatures. The buildings burned for three months. Thousands [of human remains] would come out, and they were pure white. They were in essence ash. Some were just bone dust, and there are remains that we'll never identify.
I understand there was criticism from overseas about how you went about your job?
We were criticized overseas for being too rigorous. But a 99.9 percent match is better than a 99 percent match. If we'd chosen [to be content] with a 99 percent match, that means with 1 person out of 100, there would be a mistake.
What was the most difficult part of your job?
Usually, forensic scientists don't deal with families. With the World Trade Center, it was different. Beginning in December [2001], we began meeting with families on a regular basis. They wanted to see the DNA profiles, know how we made the identifications, see pictures of the remains. They were always kind of hard to show—some were grotesque. In April and May of 2002, we were making a lot of IDs every month—75 or 100 a month—but it was clear to me that some time in the future those identifications would dwindle. When this began in 2002, we began talking about it with families. We explained that they had to be prepared for this.
How did the families react to that news?
It's like anything else. People just want to know what the facts are. They want there to be no secrets, for you just to be honest with them to the best of your knowledge. Governments still haven't learned that lesson. The decision was made in January 2005 that we just weren't getting any more IDs. You reach the limits of science. It doesn't mean you're giving up, but you have to stop until you have better technology.
What surprised you as you went through this process?
There were funeral home directors who didn't want to hurt someone's feelings. So a family would ask how much [of their relative's remains] did the funeral home get back? There was a woman who was told that her relative was 90 percent there, but then she was called and told that there were more remains coming in. She asked what was going on, and she learned that she probably had less than 50 percent of the remains of her loved one. The funeral director probably thought it would make her feel better, but she was devastated.
Were you able to identify the terrorists?
We identified three of the terrorists. There was the thinking that both planes exploded, and people would be gone but apparently not. When the planes exploded, the fragments were spread around and didn't all get caught up in the fireball. We asked the government for [DNA] profiles of the terrorists.
How did the government get the DNA profiles of the terrorists?
They never told us, but they probably knew where they'd lived in various cities around the world and collected personal items from these people.
Sounds like the job took its toll on you emotionally—as it would anyone.
There was one family member who would ask me regularly, "Did you find Mommy yet?" I crossed the line from objectivity to subjectivity. Eventually, I had a heart attack [in May 2003]. The thing is, you ignore it. You put it off, and you put it off, and you see other people going to counselors. You don't feel bad—your day is extended by five or six hours, but you deal with it. Then something goes. It's a very insidious, violent killer, stress.