Frankie shifts on her seat. "After I'd issued these results, the attorney general's office asked me to research the findings in light of Father Szyszynski's medical records. Seven years ago, he'd had a bone marrow transplant, which means, basically, that his blood was on long-term loan . . . borrowed from a donor. It also means that the DNA we got from that blood-the DNA that was typed to match the semen in the underwear-was not Father Szyszynski's DNA, but rather his donor's." She looks at the jury, making sure they are nodding before she continues. "If we'd taken saliva from Father Szyszynski, or semen, or even skin-anything but his blood-it would have excluded him as a donor to the semen stain in the child's underwear."
Quentin lets this sink in. "Wait a second. You're telling me that if someone has a bone marrow transplant, they've got two different types of DNA in their body?"
"Exactly. It's extremely rare, which is why it's the exception and not the rule, and why DNA testing is still the most accurate kind of evidentiary proof." Frankie takes out another lab report, an updated one.
"As you can see here, it's possible to test someone who's had a bone marrow transplant to prove that they've got two different profiles of DNA. We extract tooth pulp, which contains both tissue and blood cells. If someone's had a bone marrow transplant, those tissue cells should show one profile of DNA, and the blood cells should show another."
"Is that what you found when you extracted tooth pulp from Father Szyszynski?"
"Yes."
Quentin shakes his head, feigning amazement. "So I guess Father Szyszynski was the one person in six billion whose DNA might match the DNA found in the underwear . . . but who wouldn't have been the one to leave it there?"
Frankie folds the report and slips it into her case file. "That's right," she says.
"You've worked with Nina Frost on a few cases, haven't you?" Fisher asks moments later.
"Yes," Frankie replies. "I have."
"She's pretty thorough, isn't she?"
"Yes. She's one of the DAs who calls all the time, checking up on the results we fax in. She's even come to the lab. A lot of the prosecutors don't bother, but Nina really wanted to make sure she understood. She likes to follow through from beginning to end."
Fisher slants a look my way. Tell me about it. But he says, "It's very important for her to make sure that she has the facts straight, isn't it?"
"Yes."
"She isn't someone who'd jump to a conclusion, or rely on something she was told without double-checking it?"
"Not that I've seen," Frankie admits.
"When you issue your lab reports, Ms. Martine, you expect them to be accurate, don't you?"
"Of course."
"You issued a report, in fact, that said the chances of somebody other than Father Szyszynski contributing this semen to Nathaniel Frost's underwear were less than one in the population of the whole earth?"
"Yes."
"You never put anything in that report qualifying your results in the case that the suspect was a bone marrow transplant recipient, did you? Because that's such a rare event that even you, as a scientist, would never assume it?"
"Statistics are statistics ... an estimation."
"But when you handed that initial report to the DA's office, you were prepared to ask the prosecutor to rely on it?"
"Yes."
"You were prepared to ask a jury of twelve people to rely on it as evidence to convict Father Szyszynski?"
"Yes," Frankie says.
"You were prepared to ask the judge to rely on it when he sentenced Father Szyszynski?"
"Yes."
"And you were prepared to ask Nina Frost, the child's mother, to rely on it for closure and peace of mind?"
"Yes."
