Jodie Picoult - Salem Falls

“Similarly, the more genetic characteristics I can give you about the evidence results in the more people I can eliminate. Therefore, when you do find a person who matches the profile, the less likely it is that someone else exists with the exact same criteria.”

“How complex is the analysis?”

“Very,” Frankie said. “By its nature, it has to be extremely sensitive.”

“What precautions do you take to avoid contamination during your analysis of the evidence?” Matt asked.

“I work on only one piece of evidence at a time, label it immediately, and close it before I begin work on the next piece. I always work on the evidence before working on the known blood samples, and clean my scissors, forceps, and work surface between samples. I change my lab coats and gloves frequently and use as many disposable supplies as necessary, so there is no carryover or contamination of DNA. Finally, I have designated samples during my analysis that contain no intentionally added DNA. If at any point in the procedure I detect DNA in these samples, I assume all the samples are contaminated, and I start over.”

The prosecutor turned around and slipped on a pair of plastic gloves. Then he held up a girl’s blouse, spotted with blood. “Ms. Martine,” he said, “do you recognize this?”

“Yes. It’s the blouse I was asked to test.”

Matt entered the clothing into evidence, and then asked Frankie to identify each swab and envelope and vial that had come from the rape kit. “After testing all these items, what were your results?”

Frankie slipped a chart onto an overhead projector. This was the point at which a forensic scientist usually lost her audience. Unfortunately, Jordan thought, grimacing, that probably wasn’t going to be the case here. The jury could see her legs, which-Jordan couldn’t help but notice-were damn nice.

Appropriately, Frankie did a striptease of the chart, revealing each line only as she spoke about it. “Line one hundred,” Frankie explained, “is everything I can tell you about the victim’s known blood sample. And each of those eight weird combinations of letters and numbers to the right is an area on the DNA chain. Think of it like that side-swiping car . . . the first column is the make of the car. The second column is the model. The third is the color . . . all the way up to the eighth column, the bumper sticker. At each location, the victim received one allele from her mother, and one from her father. For example, at the CSF1P0 location, Ms. Duncan inherited a type twelve from each of her parents.

“Line two hundred is the defendant’s known blood sample. Each pair of numbers at those eight loci are alleles he inherited from his mother and father.” She pointed to the row beneath that. “On the shirt Mr. Houlihan held up, I extracted DNA from the bloodstains. You’ll see that at each location, the profile of the stains matches the profile of Mr. St. Bride.”

“How many other people might have a profile that matches the evidence?”

“It’s not possible to DNA-type everyone in the world, so I apply a mathematical formula that helps me predict the answer to that question. According to my calculations, that profile is found only once in greater than six billion, which is the approximate population of the world.”

“Can you explain the next row to us?” Matt asked.

“I know that the DNA profile detected under Ms. Duncan’s fingernails is consistent with a mixture, because at certain locations, there are three numbers-and a person inherits only two alleles. This isn’t surprising. Ms. Duncan can’t be eliminated as a possible cocontributor to the genetic material in this mixture, since I expect cells from her own hands were present. Of particular interest is whose DNA is mixed with hers. And based on the numbers in the profile of Mr. St. Bride-row two hundred-he cannot be eliminated as a cocontributor.”

“What would have eliminated him, Ms. Martine?”

“If a number came up at a location that was nowhere in his own genetic profile.”

“But that isn’t the case in this particular mixture?”

“No,” Frankie said. “It’s two hundred forty million times more likely that the defendant is the cocontributor to that sample than a randomly chosen individual in the population.”

“And the thigh line?”

She frowned. “That was a sample of semen, found on the thigh swab. Here, two locations I tested yielded inconclusive results.”

“What does that mean?”

“There wasn’t enough DNA present to profile all eight loci,” Frankie said. “In the remaining six, Mr. St. Bride could not be eliminated. It is seven hundred forty thousand times more likely that Mr. St. Bride is a cocontributor to the semen sample than another person chosen randomly from the population.”

“Thank you, Ms. Martine,” the prosecutor said.

And the jury foreman winked.

First, the cat died.

Now, it wasn’t such a big thing, taken by itself. Magnolia had been suffering with diabetes for three years, and twelve was pretty old for a cat. It had happened, her mother said, while Chelsea was at court, testifying on behalf of poor Gillian.

That afternoon, her little brother had fallen off a jungle gym and broken his arm in three places.

“When it rains,” her father said, “it pours.”

But they didn’t know about the Law of Three; they didn’t understand that all it took was one pebble to start an avalanche of dynamic proportion. What you did came back to you triplefold-both the good . . . and the bad. Chelsea wasn’t sure how much of that shit she believed, but she did know some things: She’d sworn an oath in a court of law and had gotten on the stand, and this was what had come of it. Her pet, her brother-by karmic proportions, she had one more devastation coming her way, to make up for what she’d done.

At dinner that night, she stared at her parents intently. Her mother had a mammogram scheduled the next day. Would it turn out to be cancer? Her father was planning on driving back to work that night . . . would he crash unexpectedly? Would she stop breathing, just like that, in her sleep? Would she wake up and find the Devil sitting beside her?

“Chelsea,” her mother said, “you haven’t touched your food.”

She couldn’t stand not knowing what tragedy was coming. Pushing away from the table, she ran upstairs and locked her bedroom door behind her and rummaged through her drawers, finally finding what she’d so carefully buried.

Could you wipe out your misdeeds with good intentions, like an abacus working in reverse? Chelsea didn’t know. But she tied the small bundle tight, with three knots. She stuffed it into a padded envelope that had come from an online CD store. She scrawled a new address across the front, added stamps, and ran out of her house with her parents’ concerned questions trailing her like the string of a kite.

She ran until she reached the end of the block, where the big blue mailbox sat. Collection times, it said, were at 10 A.M. and 2 P.M. With shaking hands, Chelsea dropped the packet into the moaning mouth of the box. She did not think of Gillian. She did not think of anything that might change her mind. Instead, she focused on climbing the slippery slope of hope, which promised her that by noon tomorrow, her life might turn itself around.

“You analyzed the pubic hair combings in the rape kit, didn’t you, Ms. Martine?” Jordan said, getting up from his seat.

“Yes.”

“What did you find?”

“No hairs with DNA foreign to the victim.”

Jordan raised his brows. “Isn’t it extremely difficult to violently rape someone without leaving behind a single pubic hair?”

“I see it all the time. We don’t normally even test pubic hair when we have DNA, since hairs can be transferred in the most innocent of ways. For example, when you went into the bathroom during the last recess, Mr. McAfee, you probably came away with other people’s pubic hair on your shoes, yet I’ll assume that you weren’t committing rape.”