sat in court and heard other evidence from the other witnesses, they might be influenced by it.’
‘So what about you?’ she demanded.
‘The pathologists are classed as expert witnesses, there to offer opinions, as well as fact. You’ll see Angus Smythe sitting there when we get back. We’re supposed to be indifferent to anything other than the scientific facts of the issues. Actually, the distinction is a bit blurred, as you heard the other two doctors being asked about whether Mrs Parker could have died of her cancer, which is really an opinion.’
He grinned at her again. ‘There are higher rates of pay for expert witnesses, but I doubt that young Lochinvar-Johnson or even Dr Rogers will hold out for a rise!’
At half past one they walked back to the Shire Hall, in case the QC wanted a quick conference again, and by the time the court reconvened they were sitting back in their places. This time, as Richard had prophesied, a new face was present on the further end of the second bench. Dr Angus Smythe, a Home Office pathologist from Oxford, was a burly Scotsman with a big red face and short, fair hair showing a hint of ginger. During lunch, Richard had said that he was a competent pathologist, though inclined to resent contradiction, being quite dogmatic in his opinions, sometimes unwilling to accept another view.
‘Fancies himself as another Sir Bernard Spilsbury, that allegedly infallible operator who dominated the business for forty years.’ Moira was not sure if Richard’s criticism was a touch of sour grapes, though she thought this would be foreign to his nature.
The butler appeared and, as the court rose, the now well-fed quartet followed the judge into their places. After the jury and the defendant had been settled, Lewis Gordon rose from his bench to call his last witness.
Angus Smythe stumped to the witness box and took the oath in a loud, gruff voice with a pronounced Scots accent. After it had been established that he was a consultant pathologist at the John Radcliffe Hospital in Oxford and was on the Home Office list of approved forensic pathologists, the prosecuting QC cut straight to the chase.
‘Dr Smythe, you were asked by the coroner for North Gloucestershire to carry out a second post-mortem on the body of Mrs Mary Parker, were you not?’
Smythe agreed and there was a brief confirmation of dates and places connected with the autopsy.
‘Why was this unusual procedure requested?’
‘Because neither the locum GP nor the coroner’s pathologist were willing to offer a cause of death, due to certain allegations that had been made by a relative,’ was the bluff response.
More questions elicited that he had been informed of the nature of these allegations and of the contents of the used syringe and the two containers found in the veterinary surgery.
‘And what was the result of your examination of the body, doctor? Were you able to determine the cause of death?’
The Scotsman gripped the edges of the witness box as if he intended to tear it apart.
‘I reviewed the dissections made by Dr Stein and agreed with all his findings. This did not assist me in arriving at a cause of death, so I took a variety of samples for examination back at my own laboratory.’
‘Did you perform these investigations yourself?’ asked the QC.
‘I did some of the analyses, and the rest were performed by my technicians under my direct supervision. The results led me to an unequivocal opinion as to the cause of death, which was cardiac failure due to the intravenous injection of potassium chloride.’
There was an excited buzz of murmuring from the public gallery, and the pencils of the reporters scurried across their notebooks.
‘In plain language, can you explain what led you to this conclusion?’ asked Lewis Gordon.
‘The samples I took included blood, urine and the fluid extracted from the eyeballs, called “vitreous humour”,’ explained Smythe. ‘I ran analyses for barbiturates, as there was a vial of sodium Pentothal recovered from the premises, but none was discovered. There was a substantial amount of morphine in the blood, consistent with the painkilling use of that drug, but it was not in a lethal range. As to potassium, it was useless to seek it in the blood, as that substance leaches from the cells after death and a high value would be meaningless, even if extraneous potassium had been injected.’
‘So how did you arrive at your conclusion that an excess of potassium had been administered?’ asked Gordon, though he knew the answer full well.
‘I said that the blood is useless because of rapid contamination from potassium in the body cells – but there is a place in the body which is insulated from this effect, where potassium remains at the same level as during life. This closed-off place is the fluid within the eyeball – and I found very high concentrations of that substance in the samples I took from both eyes.’
Again sibilant murmurs ran around the court, causing the judge’s head to jerk up in disapproval.
‘You are sure about this, doctor? Absolutely sure?’ asked the prosecuting counsel, wishing to fix the vital point in the minds of the jury.
‘I am in no doubt at all, sir,’ grunted Angus. He shuffled some papers on the edge in front of him and stabbed a big finger at one page.
‘The normal potassium level during life is about twenty milligrams in each hundred cubic centimetres, but my analyses revealed an average of no less than fifty-eight!’
He looked up and glared at the jury defiantly. ‘The tests were run in duplicate on the fluid from both eyes and all four results were within the expected limits of analytical error.’
He tapped his papers together into a neat sheaf and waved them at the court. ‘There can be no doubt at all that high potassium level – three times the normal amount – could only have been attained by a considerable amount of the substance being injected into the bloodstream, thus finding its way into the eye fluid.’
Just to seal the fact in the minds of the jury, Lewis Gordon added a supplementary question. ‘You say that the only way potassium could get into the eyeballs would be from an injection. Do you exclude any other means, such as taking potassium by mouth?’
‘Absolutely!’ snapped the pathologist. ‘Potassium is present in all kinds of food, especially fruit. It is even given as a medicine for bladder and kidney infections, but it is selectively absorbed and excreted, and its concentration in the blood is regulated within a very tight range, so that it could never reach these very high levels that I found in the eye fluid.’
‘How does potassium chloride cause death, Dr Smythe?’
‘It poisons muscles, causing irregularity of contraction. The most immediate effect is on the heart muscle, disturbing the rhythm of its beat.’
The prosecuting barrister pursued these matters in more detail, to emphasize the serious and indeed lethal effects of the substance. He led Angus Smythe to confirm that death from an injection of a large amount of strong potassium chloride solution would kill within minutes.
‘That is why vets use it to put down animals,’ he said gruffly. ‘They usually precede it with an injection of Pentothal or some other barbiturate, to literally put the animal to sleep, as the effects of potassium, though very rapid, can be distressing as the heart fails.’
Final questions elicited the fact that Dr Smythe discounted the presence of the advanced cancer as the cause of death. ‘There were no catastrophic complications, like an internal haemorrhage or a pulmonary embolism – that’s a clot passing to the lungs. And given the potassium findings, there is no need to invoke the general effects of cancer, advanced though that was.’
Lewis Gordon spent a few more minutes questioning the dogmatic Scotsman, though what he was really doing was covertly going over the same ground, intent on impressing on the jury that this was the crux of the evidence, that Mrs Mary Parker was virtually awash with potassium, which could only have been the sole cause of death. He pressed this point as far as he dared, until he sensed that the judge was beginning to get restive with his attempts at repetition.
‘That is the prosecution case, my lord. I am calling no other witnesses,’ he said, with an air of finality that suggested that nothing else was required for a guilty verdict.
Mr Justice Templeman peered down over his glasses at the defence counsel.
‘You wish to cross-examine, Mr Prideaux?’
Nathan rose to his feet and smiled almost ingratiatingly at the judge.
‘I do indeed, my lord, but I would like to crave your indulgence concerning the order in which we proceed.’
