“You looking at that impressive pile of case folders?” D.S. asked, his amused voice wrapping around the wall adjoining their offices.
“Yeah, I can’t even get my damn door all the way open. You gotta come see the size of this.”
“Don’t have to; who do you think put most of them there?”
Kel stood for a moment before tossing his backpack across the room onto a small couch—it, too, was piled high with administrative past-dues and research projects put on indefinite hold. Not a day went by that he didn’t promise to give it some long-overdue attention as soon as he finished with whatever bag of cats he was currently sewing up. The problem seemed to be that there was an endless supply of cats and a finite source of bags. He eased around the door, kicking the accumulated folders enough to the side to open the door fully, and then he stepped over the pile and walked straight to his desk. He wasn’t even going to pick the case files up, he decided. He’d often wondered how high the pile could grow if left untouched; maybe it’d start to compost and the bottom layers would turn to potting soil. His wife would like that. She was from the country and had not quite adjusted to the poor volcanic, almost pure iron oxide, soil around their home in Hawaii.
As he was settling in behind his desk, trying vainly to recollect where he’d left off on his office-reclamation efforts on Friday, D.S. called out from the next room.
“Hey, Kel, you have the sound of a man who needs some good news,” D.S. said as he casually walked around the corner, hands in his pockets, into Kel’s office. He stepped over the pile of folders on the floor as if they were a rain puddle on the sidewalk and pulled up a chair in front of his boss’s desk. In addition to being a little shorter, D.S. was also a little older than Kel. They had little in common, aside from blue-collar roots and having started work at the Lab within a few months of each other. Still, they had gotten along well from the start, and had come to rely on each other both personally and professionally.
“You want the good news or the not-so-good news first?” he asked. “Your choice.”
“I don’t believe you said anythin’ at all about bad news,” Kel said, looking up momentarily.
“I didn’t say ‘bad,’ that’s your term. I prefer to call it, ‘not-so-good.’”
Kel didn’t respond, at least immediately, and he took his eyes off D.S. Instead he scanned his desk slowly back and forth trying to find the loose thread that would successfully unravel the Gordian knot of mounded paper. There was none. He thought of Alexander. What had he done? He’d cut the knot. With that inspiration, Kel took his left forearm, raked a corner of his desk free—calving a small avalanche of papers to the floor—propped both feet in its place, leaned back in his chair, smiled, and said, “Give me the good first.”
D.S. nudged the pile of paper tailings on the floor with his toe. “Well.” He cleared his throat. He cleared his throat frequently, not so much out of need or nervousness, but out of habit. “Getting back to the Trimble and Evans case. Evans is still missing, and the DNA from the remains here in the Lab doesn’t match him…remember?” He paused and nodded his head forward, arching his eyebrows.
Kel mimicked the gesture and replied, “I believe I remember.”
D.S. gave a look to suggest this was not an unreasonable question on his part. “Just checking. You were pretty zombiefied last week when you got off the plane.”
“Zombiefied, perhaps, lobotomized, no. Please go on. And remember, this is supposed to be the good news.”
“Right. Good news.” He cleared his throat again and crossed his arms. “Remember that you wanted the DNA sequence from the bone here in the Lab compared to the Trimble family DNA. In case we were dealing with left-over parts of that guy.” He paused again.
“Please, D.S., do try and take all day with this—it’s not as if either one of us has anythin’ else to do this mornin’.”
“Be delighted. The fact is, we requested AFDIL make the comparison last week, right after we got the no-match to Evans. Figured, like you did, that if it isn’t Evans, then it’s probably unrecovered parts of Trimble. And the good news—because you said you wanted the good news first—is that the results are in. We had an e-mail from AFDIL waiting for us first thing this morning. How’s that for efficiency?”
“Consider me impressed. That’s the good news?”
“Ahhh, yeah, that would be the good news. That we got an answer.”
“And the bad news would be?—I think I can see this one drivin’ straight down the center of the road.”
“Yeah, you probably do. The bad news is that the DNA from the remains we have here doesn’t match the Trimble reference either. Both Evans and Trimble can be excluded on the basis of the DNA.”
“Not extra parts, huh? How do you explain that?”
“Don’t know that I can.”
Kel considered this briefly and then asked, “How good was the recovery? Do we feel good about the archaeological context?”
“I feel very good—Caroline did the recovery, and she knows what she’s doing. It’s the right grid coordinates, squares up with a good after-action report by the Marines who policed up the battlefield in 1966 a couple of days after the loss. We were definitely in the right spot. On top of that, we got a dog tag for Evans at the site, remember? That confirms the location. The recovery is solid.”
“Anybody else lost at the site? Or just Evans and Trimble?”
“Just those two. Some other guys—a half-dozen maybe—lost in the firefight, but they were some distance away, according to the wartime report, and despite some advanced decomp, they were found in pretty good shape. No chance of a misidentification, as far as I can tell. No chance of leaving behind any parts either.”
“How about the DNA? Any chance it was contaminated?” It was always a small chance. Both the CILHI and the Armed Forces DNA Identification Laboratory had stringent protocols that minimized the potential for contaminated DNA samples, but it was always a remote possibility.
“AFDIL says no. Controls are good, all four bone samples we submitted gave the same sequence—with full sequence data—and it doesn’t match the DNA from any of our staff or theirs, so it doesn’t appear to be the result of contamination. DNA looks as solid as the recovery—which is solid.”
Kel leaned back and stared at the acoustic ceiling tiles as he thought. The DNA lab was working with mitochondrial DNA, and that presented problems. Mitochondrial DNA—mtDNA—is the redheaded biological step-molecule when it comes to the press and public. Cable television is filled with news stories and documentaries involving the extraordinary power of nuclear DNA to fight crime, right injustice, and cure genetic disorders. Consequently, most people have absorbed at least a rudimentary understanding of nuclear DNA’s shared origin—how half comes from the father and half from the mother—which is why it is of such use in forensic settings; a little bit of this, a little bit of that, shake and bake and scramble a bit more, and the result is an individual with such genetic rarity that it approximates uniqueness. But mtDNA is different. Floating around in the watery cytoplasm outside the nucleus—largely unnoticed by the press and cable television viewers—are little bean-shaped organelles called mitochondria, whose function is to supply energy to the cell. Each carries its own circular ring of DNA—mtDNA. The difference between nuclear and mtDNA is not in its structure but in the latter’s lack of a shared parental origin. As the fertilized egg cell divides, the nucleus divides and so does the combined maternal and paternal nuclear DNA. But the cytoplasm contains only the mother’s mitochondria—the father’s mitochondria being discarded in the tail of the sperm the way a Saturn rocket discards its booster stages—and when the cell divides, only the mother’s mtDNA is available. The result is a mitochondrial identity that is not unique but is shared through maternal lines, in much the same way that last names follow paternal lines. Individuals sharing maternal blood—mother, siblings—have the same mtDNA, barring the occasional mutation.
It is this shared bloodline that pre
sents the promise and the problem for forensics. The stability of mtDNA allows it to be applied to very old cases; cases for which no direct reference sample may be available. It is ideal for helping to identify U.S. soldiers who died thirty, fifty, even sixty years ago, and for whom direct or parental blood samples may no longer be obtainable. Using mtDNA, maternal relatives not even born when a soldier was lost can supply a blood sample for comparison.
“How about the family references?” Kel knew he was grasping, but sometimes a family member turned out to not be related quite the way they thought they were. It was a delicate issue, but one that cropped up nonetheless. “Any chance one of the relatives isn’t a real maternal relative?”
“Brian doubts it,” D.S. continued, referring to Brian Smith, the CILHI’s DNA coordinator. “AFDIL does too. The samples for Evans are from his mother and brother; the Trimble samples are from his mother and a maternal aunt.”
“Yeah,” Kel considered, “but if one of those mothers isn’t the birth mother, then the other relatives don’t matter. Maybe one of them—Evans or Trimble—was adopted. We had a case like that a few years ago, in 1997 or ’98, remember it?…air force lieutenant shot down in Laos…you remember? Turned out he was adopted, and his elderly adopted mother didn’t realize it made a difference for DNA—just sent the blood sample in and didn’t think twice about it. Took almost a year to put that puzzle together, as I recall. Why don’t you have Brian e-mail the marine and navy casualty offices and get them to double-check on whether we might be dealin’ with a situation like that?”
“Okay, but…”
“But what? You don’t think the chance of an adoption is very good? Well, neither do I, but we need to tie that loose end up just to make sure. I’m not hearin’ any other explanations, am I? You know as well as I do that sometimes these older parents don’t really understand why they’re givin’ a blood sample, and if the casualty reps didn’t fully explain the procedure to them, they may not have realized the need to divulge an adoption. With that generation, adoptions are sometimes very private matters.”
“It’ll probably take awhile, but sure, I can have Brian do it. You know as well as I do, though, that it’s unlikely either of these guys was adopted. That isn’t going to answer this one. It simply isn’t them, either one of them.”
Kel leaned back farther in his chair and briefly stared at the ceiling of his office before closing his eyes.
“Any other suggestions?” D.S. asked.
“Yeah, just beat me with a stick—a big, red stick.”
Chapter 9
Armed Forces DNA Identification Laboratory, Maryland
MONDAY, AUGUST15, 2005
Thomas Pierce was the first civilian director of the AFDIL—the Armed Forces DNA Identification Laboratory in Rockville, Maryland. He’d started there almost ten years earlier, first as an active-duty air force lieutenant colonel, then as a colonel, and now as a civilian. By anyone’s yardstick he had done a remarkable job, which is why when his retirement date had rolled around he’d simply left work on a Friday, hung his uniform in the back closet, and returned in civilian clothes on Monday. The conversion to a civilian directorship had been handled so smoothly that no one really noticed a change except for the fact that the few military personnel around the Lab had taken to calling himTom rather thanSir .
Pierce was remarkably even-tempered for a man his age, a trait that made him easy to respect and almost impossible not to like—unless you really worked at it. But most people regarded his greatest skill as his ability to broker agreements, and not just to simply broker them, but to do so with so little visible effort that you didn’t realize that you’d gone and signed up to something you’d vowed never to even consider—until you were at home taking a shower. Not big agreements like SALT treaties or Mideast peace accords; his gift was in crafting the small interpersonnel and interoffice ceasefires that made the gears of government mesh quietly.
It was, in fact, largely his reputation as one of the last honest men in Washington, a man devoid of any fractious personal agenda, that had recently ended the CILHI-AFDIL turf battle that had been raging like a miniature Civil War for as long as anyone in either organization could remember.
People knew his strengths. More important, he knew his strengths—and he didn’t undervalue them.
Ironically, at the same time as the CILHI and the AFDIL had set aside their differences and agreed to share the playground toys, the AFDIL and the FBI had renewed a protracted internecine war over the proprietary responsibility of the mtDNA reference database. At issue was the fact that the two DNA labs shared some of the same sequence reference data.
If the shared maternal lineage is mtDNA’s forensic strength, it also presents the biggest problem. How to gauge the strength of a mitochondrial match? If mtDNA is not unique to individuals, what is the probability that two individuals may match by mere chance alone? The solution is to estimate the commonality of a given sequence and then calculate the probability of that sequence occurring in the context in question, and the way to estimate commonality is to create an immense database of mtDNA sequences from around the world, and then to compare the mtDNA sequence obtained from a test sample to the database—something like calculating the commonality of the last name “Smith” by counting the number of occurrences in a phone book and then dividing by the total number of names in that phone book.
But in science, data are currency, and currency is not generally shared easily. Which is how a simple database had managed to become a major point of contention between the two organizations.
Actually, the AFDIL had begun the database project in large measure to support the CILHI’s identification mission, the CILHI being the largest user of mtDNA testing for identification purposes. Over the years, however, the FBI had assumed a greater and greater involvement as the use of mtDNA increased in traditional forensic cases, and the Bureau had taken over the responsibility of ensuring that proper database protocols were being followed. To no one’s real surprise, eventual data discrepancies arose, fingers were pointed, and the rift between the AFDIL and the FBI developed and widened. For a while the gap had become so great that the two organizations ran separate, but parallel, databases, neither one able to access the other’s data. Recently, however, the two labs had agreed to attempt reconciliation and return to joint administration.
But cracks were again beginning to develop, and it came as no surprise to Pierce when he got a call from James Scott, from the FBI, requesting a meeting. Apparently it was time to doctor some sores.
“You’ve moved up in the world, got yourself a window, I see,” James Scott said as he walked into Pierce’s office. Thomas Pierce had recently shuffled some staff around and had moved his own office in the process. Previously he’d had a spacious, but windowless, cell deeper in the bowels of the building. Now he had a corner office with a view of the busy interstate.
“Yeah, ’bout time.” Pierce smiled. He rose from his chair and extended his hand. “You know government workers, we’re required to stare blindly off into the distance most of the day. I’m important enough now that they’ve given me more distance to stare into. Sit down, Jim, sit down. How’s it going with you?”
“Oh, you know the drill. What’s that they say in Asia? Same, same, only different.” He took a seat across the desk from Pierce and withdrew a thin stack of computer printouts from the briefcase on his lap. He placed the papers on the edge of the desk and snapped the case shut before continuing. “You’re probably wondering what I wanted to talk about.”
Thomas Pierce smiled. Scott was a true Yankee from Connecticut and had never mastered the diplomacy of small talk. He was curt to the point of annoyance.
Scott continued without a break. “Truth is, there are several things, but the first one is kind of a sticky issue. Maybe we should speak in hypotheticals.”
“I agree in theory,” Pierce said, still smiling. Despite some professional differences, Pierce found James Scott simultaneously hard to n
ot like and impossible to stand. Even his humorlessness had a level of efficiency that begged admiration.
Scott’s eyes flicked up from the papers he was shuffling and briefly caught Pierce’s own. He knew that he was often the source of other people’s amusement, but he was persistently at a loss on how to tell when or why. He didn’t know now. “Good,” he continued. “Okay, let’s just say…”
“Hypothetically.”
“Right, hypothetically. Let’s just say—hypothetically—that the Bureau’s working a cold case…”
“So you’re not really working a cold case…this is hypothetical.”
“Yes. I mean…no, we are. We are working an old case, and we sequenced some mito from it. Now, here’s the hypothetical part. Let’s say that we got a very unusual sequence from the evidence—okay?”
“Okay. That’s supposed to be good. Rare is good.”
“Yeah, well…right. So, we got an unusual mtDNA sequence—unusual enough that it sticks in your mind, okay? Okay. And let’s say that this unusual sequence also turns up in the mito database. You with me?”
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