“Ladies and gentlemen,” Paul said to the jury. His voice was bright, enthusiastic. “I do hope that you all had a good lunch. Now, no doubt you’ll be pleased to hear I am approaching the final part of my defence.” Most of the members of the jury smiled as he said this. “I would like to call Dr Klein back to the witness stand.” The now familiar figure of Dr Klein made her way to the witness stand. I looked up at the public gallery as she settled herself into her seat, and I could see Andy and Jacob sitting next to each other, Tommy and David to their left, but I couldn’t see Big Joe or Robert’s parents. I scanned across the faces of the other people in the public gallery, wondering who they were, when I saw a familiar face. Mr McLoughlin, the prison guard. As I caught his eye, he half raised a hand. Laura had instructed me several times not to engage with anyone in the public gallery, but I risked a nod to acknowledge his greeting, anyway.
“Now, Dr Klein, you are still under oath, so we won’t need to swear you in again,” Paul said for the benefit of the jury.
“Thank you,” Dr Klein replied, her trademark smile still present. Just as when she had first sat down in the courtroom, I expected her to pull out some knitting needles.
“I want to talk this afternoon about the mechanics of Mr Wainwright’s injuries,” Paul said. “Now I know that you weren’t present at the post-mortem, but can you confirm that you are up to speed on this issue?”
“Absolutely. The pathologist’s notes and slides were extremely well done. I was able to get all the information that I needed from them.”
“Could you describe Mr Wainwright’s injuries, in general terms?” Dr Klein checked her notes before replying to Paul’s question.
“Yes, of course. According to the post-mortem report, there were two areas of injury to Mr Wainwright. The most obvious of these areas was obviously to Mr Wainwright’s head, but the pathologist also noted some old bruising to his ribcage.”
“Old bruising?” Paul asked. “How old exactly?”
“Yes, now it’s always difficult to be too accurate with the time of partially healed bruises, but as a rough estimate the pathologist suggested two to three weeks.”
“Which would mean that those injuries were inflicted at some point in the weeks before he was killed?”
“Yes, that would be correct. But it’s not possible to be more specific than that.” Robert’s old injuries had been brought up in the original trial, but Miss Revell had argued that it was impossible to ascertain how Robert had sustained them. I looked across at her, wondering if she would raise the same objection again, but she remained silent.
“Did Mr Wainwright have any other injuries at all, other than the bruising to his chest and the head injuries that we are going to explore in a moment?”
“No, he didn’t,” Dr Klein replied.
“Did he have any defensive injuries to his hands?”
“No, it was just the bruising to his chest and the head injuries.”
“Thank you, Dr Klein,” Paul said. “But before we get to those particular parts of the jigsaw puzzle, could I ask you first to tell the jury a little bit about what happens when somebody is hit around the head with a blunt object? Such as a baseball bat?”
Dr Klein turned to face the jury, smoothing out a wrinkle on her tweed skirt with the palms of her hands.
“Ladies and gentlemen, I will try my best to explain this in straightforward language. You see, the head can be thought of in the same way as an egg. If you consider an egg, it has a hard outer layer or shell. The head has a skull. Inside the egg is the important part, the yolk. Or the brain. Finally, surrounding the yolk is a protective fluid, or egg white, which is very similar to the liquid the brain floats in. It’s called cerebrospinal fluid.” Dr Klein paused and looked at each of the jurors in turn. I figured that she was making sure they were all keeping up. From where I was sitting it looked as if they were. “Now imagine that you tap the side of an egg. Quite hard, but not hard enough to break the shell. The yolk is protected by the egg white, and while it may wobble around inside the shell, there is enough fluid to protect it from too much damage. If you hit the side of a human head with a blunt object such as a baseball bat, it has exactly the same effect.” I saw several of the jurors nodding at Dr Klein’s explanation. “The brain is protected to an extent by the cerebral spinal fluid it floats in, as the yolk is by the egg white.
The effects of this wobbling, for want of a better word, will vary according to several factors. The force of the blow is probably the most important factor, but others are the direction of the impact and where the impact hits. For example, a blow to the side of the head can cause various internal injuries without the skull itself being broken.” Dr Klein paused, again surveying the jurors. Although a few of them were frowning, they all seemed to be following along. I half expected one of them to put their hand up at some point as if they didn’t understand, like children with a teacher.
“Because the brain is mostly fluid, any force travels through and around the brain tissue, often in small swirling currents or eddies. When the skull remains intact, this force is reflected within the cranium as it has nowhere else to go. This bounces around inside the skull which can set in motion a sequence of events inside the brain tissue. Perhaps the most dramatic of these events is immediate unconsciousness.”
“So, it is quite possible to hit somebody with a baseball bat, without breaking the skull, and for them to be rendered unconscious immediately?” Paul asked.
“Yes, indeed,” Dr Klein replied. I thought back to the night I attacked Robert. That was exactly what had happened. He had gone down like a sack of potatoes when I’d hit him.
“If an individual is struck as described, and is lying unconscious, what then is happening inside their brain?” Paul asked.
“Well, a lot of that depends on the factors I have previously mentioned, I would expect that there might be a degree of bleeding within the brain. This might be quite obvious bleeding, such as a subdural haematoma or a bleed in between the layers of tissue which surround the brain. Or it could be microscopic in nature.”
Miss Revell got to her feet as Dr Klein finished speaking.
“Your Honour,” the prosecutor said, “the witness is quite clearly speculating.”
“Your Honour,” Paul barked. “I fail to see how an expert witness in blunt cranial trauma who is describing the pathological and physiological responses from a blow to the head can be said to be speculating.”
“I agree. Thank you, Miss Revell,” Judge Watling said. Miss Revell sat back down in her chair, looking defeated. One of her colleagues put a hand on her shoulder and leaned forward to say something in her ear. Whatever he said, Miss Revell didn’t agree with it and her face turned even sourer.
“Dr Klein, thank you. Would you now explain to the jury what happens when blows which are hard enough to break the skull are delivered?” Paul asked.
“Yes, certainly. The egg analogy is another useful one in this case. If you imagine hitting an egg hard enough to break the shell, the egg white then stops protecting the yoke, or the brain. Once the protective layer of the skull is breached, the brain can be disrupted much in the same way that an egg yolk can break, spilling its contents. If the area of disruption includes an area of the brain which is crucial to life itself, then this can have fatal results.”
On the jury bench, Ella was holding a tissue to her mouth, and Minnie had gone a deathly pale colour. As I watched, the juror next to her leaned across to comfort her. I wondered if I should say something to Laura, or get her attention somehow. The poor woman on the jury bench didn’t look well at all.
“The hypothalamus is one such area,” Dr Klein continued, oblivious to the plight of Gloria and Minnie, which surprised me. “It controls the heart rate and respiratory rate. If the damage to this area is severe enough, then the heart stops beating and respiration ceases. Life itself ceases.” As Dr Klein spoke these words, there was a genuine look of sadness on her face. I glanced back across the jury to see many of them frowning, one or two wearing the same expression as Dr Klein’s. Ella let out a loud sob, and the juror next to her put her arm around her shoulder.
“Your Honour,” Paul said in a soft voice. “Perhaps now would be a good time to take a break?”