Red Herring (19 page)

Joe was already trying to put him at ease. “No, no. That’s fine. Totally understood. Not a problem.”

“All right.” Shepard nodded and moved to the next slide, this one vaguely familiar to the cops, if not in fact intelligible. “This is actually not your standard DNA profile,” he explained. “We had to resort to something a little fancier called Copy Number Variation to compare what little DNA was on the underwear to whoever handled that electric cord last—there simply wasn’t enough material to do otherwise—much less a standard DNA profile. And yes,” he added quickly, “we did run it against Mary Fish’s and Elise Howard’s genetic code to rule them out; it’s definitely someone else, a male.”

“You found DNA on the underwear?”

“Next up,” Shepard said, smiling. The next slide showed that article of clothing. “At first blush, we were ready to categorize this alongside the suicide note. The comments David left for us indicated the working theory of the false rape, and that the underpants had been pulled down solely for staging. In the old days, that would’ve been it, and little time would’ve been wasted running tests.”

He turned toward them like a happy snake-oil salesman, his eyebrows high and his expression bright. “But no longer. Infrared spectromicroscopy lets us see things we never thought possible. Following the theory of the case, I worked out in my mind how the victim was
attacked, laid out, and then positioned, and calculated that only a finite area of the underwear would have been available for the killer to pull down around her ankles.”

As he was speaking, he was showing various aspects of the garment, once again ending up with what looked like a microscope slide. “The key turned out to be the same mineral and chemical signatures that we lifted from the electric cord. Once we found them, we were able to extract more touch-DNA.” He hit his keyboard dramatically with his finger. “And voilà. A profile perfectly matching the Copy Number Variation sample from the Mary Fish scene. Proof that the same man was at least at the scene of both murders. Agreed?”

Joe was momentarily caught off guard, suddenly realizing that Shepard was actually looking for an answer.

“Absolutely,” he blurted. “Incredible work.”

“Sadly,” Eric added now, “I wasn’t able to extract anything beyond gender from either sample. They’re just too small. Still, with any luck, you’ll be able to run this through your state data bank at least and secure a hit.”

“Fingers crossed,” Lester said softly, his inflection betraying his doubt.

“All right,” Shepard resumed, advancing his show with another image. “Down to the last victim, young Bob Clarke. Here, the paydirt was with the supposedly wiped bottle and the truck bumper.” He cut a slightly disapproving glance at his colleague. “Eric already mentioned how, when the bottle was wiped clean, the cloth or rag used exchanged its trace evidence for the fingerprints that it erased. The report I read said that no rag was found at the scene, is that right?”

“Correct,” Joe told him.

“Then we assume, with some small risk of error, that the killer
used his own. This assumption is borne out by what we did find on the bottle’s surface.”

“Don’t tell me,” Lester commented. “Oil and acetylene.”

“Among other things, yes,” Shepard agreed, his earlier glee still somewhat dampened by Marine having stolen his surprise. The reaction reminded Joe of how childish humans could be, regardless of their educational achievements, and maybe—sometimes—because of them.

“Other things?” Joe prompted.

Shepard’s eyes widened slightly. “Ah, yes. Well, not surprisingly, a rag kicking around on the floor of a vehicle or even a glove box, if that’s where he kept it, will pick up a lot of microscopic debris. Still”—the prior shine in his eye made a grudging reappearance—“I was able to locate the sawdust. No gunpowder, though.”

Joe smiled broadly, in part to encourage him. “I can live with that. Oak, again?”

“Not only that,” Shepard conceded, gaining momentum, “but mixed in with the oil were minute metallic flakes, symptomatic of the used engine oil found in every car. My guess is that whoever this is used the rag to either wipe his dipstick or to clean around the pan lug when he last changed his oil. The beauty with that is the same as with DNA—once you locate your suspect’s vehicle, we should be able to connect the old engine oil on the bottle to the oil in that car’s engine.”

“Cool,” Lester murmured.

“Which brings us”—Shepard moved to another slide—“to Bobby’s truck. Here, you must pass along my kudos to David Hawke and his staff, who really did an extraordinary job with all of this material, to be honest. But the truck bumper was tricky and especially well done.”

The picture was of the bumper fragment Joe and Lester had
brought with them. Shepard pulled a pen-sized laser pointer from his breast pocket and began moving its hot red dot across the image.

“What we noticed on this otherwise unremarkable surface, employing a variety of light sources, was that it had recently been disturbed, I think we can now safely say by the application of a second bumper used to push Bobby’s truck off the road.”

Lester was scrutinizing the picture and clearly seeing nothing at all. “You’ve got to be kidding.”

“Actually, no,” Shepard answered him. “The photograph doesn’t do the evidence justice, to be sure, so it’s not quite as amazing as you might think. In fact, there are a couple of small aberrations visible to the trained naked eye, but I emphasize the word ‘trained,’ which is where David comes in. As you
can
see, this was not a new bumper, and it had clearly seen better days. He was able to distinguish old injuries from new, which gave us this . . .”

A new slide appeared.

“Which is what?” Lester asked of the chart before them.

“A readout of the deposits on the surface of the bumper,” Shepard informed them. “Again, similarly to most of the samples we’ve been discussing, the assemblage of artifacts constitutes a unique fingerprint of the offending bumper—everything from transposed dirt, soap from a recent car wash, more oil, our friend the acetylene, and sundry other items of little interest either because they’re so common, or because we can’t link them to anything.”

“Acetylene traces were on the bumper?” Joe asked.

Shepard looked at him appraisingly. “Yes. I was struck by the same thing. What do you make of it?”

“That the user of the torch and the car were in proximity,” Joe said, “implying that the acetylene isn’t being used in a commercial environment, but a home one, like a garage.”

Marine smiled. “That’s what we were thinking.”

“What do we do with that?” Les asked.

“Nothing yet,” Joe said. “But I still like it.”

“I ought to add something about the oil in this instance,” Shepard then pointed out. “It’s not engine oil.”

“Oh?”

“It’s much lighter, more refined. I really had to dig around to find an explanation.”

“Did you find one?” Joe asked him.

“Not really.”

Joe smiled. “You said you hadn’t been to Vermont. We use light oil to undercoat our cars, to stave off rust from road salt.”

Shepard laughed. “That’s it. I even found some salt residue.”

“It’s been snowing up there.”

Shepard nodded. “How wonderful. All right, then. There you have it.”

He again sat back in his chair, this time indicating that his role had reached an end. Joe read the body language and expressed his thanks. “Dr. Shepard, this has been incredible.” He cast a look at Eric Marine before continuing. “I know we’re not through—we still have the three drops of blood—but this alone has already given us a huge advantage. The guys back home will hate me when I hand them all this extra homework, but it’s exactly what we were hoping for. Many, many thanks.”

He looked at Marine again as Shepard went to studying his knuckles self-effacingly, but with a pleased expression. “Dr. Marine?”

Eric happily pulled the laptop toward him. “The blood. Let’s hope this will be a kind of cherry on top of Wayne’s ice cream sundae.”

He fiddled with the program briefly and brought up his own set of pictures, all of them charts and graphs that both cops recognized, at
least in theory, from past exposure to DNA explanations, often rendered in court to equally bewildered juries.

“As you know,” Marine began, “we were given three samples, one from each murder scene. We didn’t know the order in which they were originally collected by your suspect, so we kept to the same sequencing order we applied to Wayne’s list,
i.e.
, Doreen’s was Number One, Mary’s, Number Two, and Bobby’s, Number Three. For reasons that I’ll soon explain, this turns out to have been a fortuitous choice.”

Like Shepard before him, he played the keyboard as he spoke, but since the image contents meant even less to the two laymen, they didn’t pay the slide show much attention. Marine didn’t appear to mind.

“Again, as you knew before coming here, none of the DNA extracted from these three samples matched the victims they accompanied, the other two people killed, or each other. They were pure stranger deposits. My objective approach, therefore, was to work from the basis that at least two out of the three did not belong to the killer, unless, of course, there are actually three killers involved, all of whom left blood samples as a form of signature.”

“Oh, Jesus,” Spinney said, half to himself. “I never even thought of that.”

“It’s unlikely,” Eric agreed. “But possible. On the other hand, it doesn’t really alter my findings, and to be honest, I’m speaking more of how I was thinking before Wayne found what he did, which seems to connect all three cases to one perpetrator. Not only that,” he added, “but as you’ll also soon find out, I’m now pretty doubtful that any of the samples belongs to our guy.”

He lit up the screen with something the two Vermonters could understand—a list.

He introduced it by explaining, “I thought about wowing you
with some of the magic we do here, and which your crime lab can only dream about. But then I realized you’d have little clue about what I was describing. That’s the reason for the separate report just for David Hawke.

“So”—he pointed at the screen—“I kept it simple. Drop Number One. He’s a male with brown eyes, chances are he’s black and—with consultation with one of my colleagues working on the NASA radiation effects team here on campus—I figure he’s being treated for an aggressive form of cancer.”

Joe let out a laugh. “You don’t have his cell-phone number?”

Marine looked pleased. “It is fun, I will admit.” He then held up a cautionary finger. “But let me say, before Wayne does, that it all comes with a caveat. The methods I used are cutting-edge stuff, some of it controversial, and none of it, as far as I know, admissible in court—except for the gender reading, of course.”

“But they aren’t wild guesses, either,” Shepard put in supportively, as if softening the implication that he might be more rigid than was reasonable.

“No, no,” Eric followed. “Absolutely not. I wouldn’t have put this forth otherwise. There is a growing body of increasingly reliable research centering on what we call EVAs, or Externally Visible Characteristics. These are traits like skin, hair, and eye color, and maybe obesity, height, and whatnot; speaking of which, gender is actually an EVA. Anyhow, the goal is to come up with some Star Trek–style device where we’ll eventually be able to put a drop in one end, and get a picture of the blood’s owner out the other. That’s all science fiction right now, of course, but we are making baby step inroads.”

“With ethnicity, for example,” Joe suggested.

“Right,” he said brightly. “It turns out some of these EVAs are easier to nail down than others, gender being one of them. Even so,
as with gender, none of it is flawless. Still, it seems that red hair and blue and brown iris color are getting much more predictable.”

“And black skin color?” Lester suggested.

“Right,” Eric agreed slowly. “To a slightly lesser degree, but I thought it looked good enough to suggest.”

“Any idea on the type of cancer?” Joe asked.

The DNA man ducked his head a moment, choosing his words. “This gets trickier. Medicinal radiation is designed to minimize damage to DNA, for good reason. Also, localized radiation is going to affect the body’s general blood supply less than radiation that’s being applied to let’s say leukemia or bone cancer. Now, of course, we can’t actually know the realities involved here, but my sources—who have a huge knowledge of irradiated blood samples—are leaning toward something long term and generalized.”

“Like leukemia?” Joe reiterated, to be sure he understood.

“Correct,” Eric reassured him, before following with, “but that could be completely wrong.”

Joe shrugged. “I’ll take it anyhow, given what we’ve got. Is that it for Drop Number One?”

Marine hit a keyboard button. “It is. This is Number Two. She’s a female with blue eyes, but that’s about it, except for the two small details that I promised to explain.”

Joe smiled at the obvious come-on. “Which are?” he played along.

“Let me proceed with one at a time, or none of it will make sense,” Eric said. “To begin with, the DNA is degraded.”

“What’s that mean?” Les asked. “The guy left the sample lying around?”

“That’s a distinct possibility,” the scientist agreed. “But I was intrigued by an additional hypothesis: that the blood was extracted from someone dead.”

“What?” Joe blurted out.

Eric held up a hand while striking another key, explaining, “This is Drop Number Three, which is not only what made me return to Number Two to consider my hypothesis, but which also explains the second unusual feature I mentioned about Number Two. Let me start by saying that Number Three is significantly degraded, far more so than Number Two. That coincidence made me consider the possible parallels between either collection techniques or—shall we say—the raw material used.”

Mimicking his colleague earlier, Wayne Shepard chuckled and muttered, “You’ll love this.”

His partner continued. “Here’s the kicker that lends it credibility: Number Three is contaminated with just a smidgeon of leftover Number Two DNA.”