“Not a lot of blood, if that’s what you mean. Frank Wallace was cut while he was standing at the front of the garage. The stain on the floor by the bed was probably from Tommy’s dog, Pippy, trying to hork up a sock.”

Sara winced. “Do you still think Tommy did this? His confession doesn’t line up with the facts.”

“Lena’s been working on the theory that Tommy took Allison out to the woods on his scooter and murdered her there. I suppose he was sitting on the cinder blocks the way you’d put a kid on some phone books at the kitchen table.”

“That sounds completely believable.”

“Doesn’t it just?” He scratched his jaw. “Have you examined Allison’s body yet?”

“I took a preliminary look at the wound. The attacker was behind her. Most knife injuries to the throat are from behind, but usually the blade is drawn across the front of the throat, oftentimes resulting in a partial decapitation. Allison was stabbed from behind with the blade going into the neck from the rear, the trajectory going toward the front of the throat. It was one thrust, very calculated, almost like an execution, then the killer twisted the blade just to make sure.”

“So, she died from the stab wound?”

“I can’t say for sure until I have her on the table.”

“But you have an idea.”

Sara had never liked giving her opinion unless she had strong medical fact to support it. “I don’t want to make assumptions.”

“It’s just us down here. I promise I won’t tell anybody.”

She was only vaguely aware that she was relenting much more easily than she should have. “The angle of the wound was designed to deliver a quick death. I haven’t cut her open yet, so I’m not sure—”

“But?”

“It looks like the carotid sheath was cut, so we’re talking an instant interruption of the common carotid and more than likely the internal jugular. They’re branched together like this.” She lined up the index fingers of both her hands. “The carotid’s job is to carry oxygenated blood at a rapid speed from the heart into the head and neck. The jugular is a vein. It’s gravity fed. It collects the deoxygenated blood from the head and neck and sends it back to the heart via the superior vena cava, where it’s oxygenated again and the whole process starts all over. You follow?”

Will nodded. “Arteries are the water supply, veins are the drain. It’s a closed system.”

“Right,” she agreed, giving him points for the plumbing analogy. “All arteries have a little muscle spiraling around them that relaxes and contracts to control blood flow. If you cut an artery in two, sever it, the muscle contracts, curling up like a broken rubber band. That helps stanch the blood flow. But, if you slice open the artery without cutting it in two, the victim dies from exsanguination, usually very quickly. We’re talking seconds, not minutes. The blood shoots out, they panic, their heart beats faster, blood shoots out faster, and they’re dead.”

“Where is the carotid?”

She put her fingers alongside her trachea. “You’ve got one carotid on each side, mirror images. I’ll have to excise the wound, but it appears that the knife followed this route, entering near the sixth cervical vertebra and traveling along the angle of the jaw.”

He stared at her neck. “How hard is that to hit from behind?”

“Allison is very small framed. Her neck is the width of my palm. There’s so much going on in the back of the neck—muscles, blood vessels, vertebrae. You would have to pause, to take a second, to aim so that you hit the exact spot. You couldn’t go straight in from the back. You’d have to go from the back toward the side. With the right knife, at the right angle, the odds are pretty good that you’ll end up opening both the carotid and the jugular.”

“The right knife?”

“I’m guessing it had a three-and-a-half- to four-inch blade.”

“So, we’re talking about a kitchen knife?”

He obviously wasn’t good with measurements. She showed him the distance using her finger and thumb. “Three and a half inches. Think about the size of her neck. Or my neck, for that matter.” Sara kept the measurement between her fingers and held her hand to her neck. “If the blade had been any longer, it would’ve exited the front of the neck.”

He crossed his arms. She couldn’t tell if he was pleased or annoyed with the visual aids. He asked, “How wide do you think the blade was?”

She narrowed the space between her thumb and finger. “Five-eighths? Three-quarters? The skin is elastic. She must have struggled. The incision is wider at the bottom, so the killer jammed in the knife to the hilt, then twisted the blade to make sure he was doing maximum damage. I’m sure it wasn’t over an inch wide.”

“That sounds like a large folding knife.”

Sara thought he was right based on the bruise from the hilt, but she told him, “I really need to look at the wound in a better setting than inside the freezer.”

“Was it serrated?”

“I don’t think so, but really, let me get into the wound and I can tell you everything you need to know.”

He chewed his lip, obviously thinking about what she had told him. “It takes less than two pounds of pressure to penetrate skin.”

“As long as the knife is pointed and sharp and the blade is forcefully thrust.”

“Sounds like something a hunter would know how to do.”

“Hunter, doctor, mortician, butcher.” She felt the need to add, “Or anyone with a good search engine. I’m sure you can find all kinds of anatomical diagrams on the Internet. Whether they’re accurate is up for debate, but whoever did this was showing off his skills. I hate to keep banging the same drum, but Tommy had an IQ of eighty. It took him two months to learn how to tie his shoes. Do you really think that he committed this crime?”

“I don’t like to speculate.”

She gave him his own words. “It’s just us down here. I won’t tell anyone.”

Will didn’t give in as easily as Sara had. “Was Tommy a hunter?”

“I doubt Gordon would’ve let him have a gun.”

Will took a moment before asking his next question. “Why not drown her? She was standing by a lake.”

“The water must have been close to freezing. There was the chance of a struggle. She could’ve yelled. My house is—was—across the lake from Lover’s Point, but sometimes when the wind was right, I could hear music playing, kids laughing. Certainly, any number of people would have heard a young girl screaming for her life.”

“Wouldn’t it be easier to cut the front of the throat instead of going in through the back?”

She nodded, saying, “If you cut the trachea, the victim wouldn’t be able to speak, let alone yell for help.”

Will pointed out, “Women tend to use knives.”

Sara hadn’t considered the possibility, but she was grateful his mind was moving off Tommy. “Allison was small. A woman could have overwhelmed her, then carried her to the water.”

“Was the killer left-handed? Right-handed?”

“Well—” Sara was going to ask if it mattered to someone who could not tell the difference, but answered him instead. “I’m assuming right-handed.” Sara held up her right hand. “The attacker would have been at a superior position, standing above her, possibly straddling her, when the blade went in.” She paused. “This is why I don’t like to make assumptions. I need to check her stomach and lungs. If we find lake water, then that means she was probably facedown in the water when he stabbed her.”