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A state of Injustice - - Dr Robert N Moles
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Go to: A state of Injustice: table of contents
Chapter Six - Time and time again
David Szach 1979
Stefan Niewdach and Alan Ellis 1992
The timing of death is important in any murder case because it helps to narrow down the range of people who could be regarded as suspects. In the Van Beelen case the estimated timing was so tight that, even though it has been called ‘scientifically unsound’, it eliminated all but Van Beelen from suspicion. But Van Beelen is not the only case in which serious questions have been raised concerning the evidence given with regard to the timing of a death. One such case is that of David Szach who was convicted of the murder of the Adelaide lawyer Derrance Stevenson. [1] Stevenson’s body was found with a gunshot wound to the head, in a freezer at his own home.
Another case in which the evidence on timing of death was important concerned the death of Gerald Warren. [2] In estimating the time of death, the pathologist, Dr Manock, took into consideration factors of blow flies and bird droppings that were not really relevant. In this case there were also problems caused by Dr Manock’s failure to identify correctly the weapon used and the manner of death.
Szach charged with murder
David Szach, 19, was in a relationship with the 44-year-old Derrance Stevenson. According to the autopsy report, Stevenson is said to have died somewhere between 4 and 5 June 1979. It appears that Szach had driven from Adelaide to Coober Pedy (about 850 kilometres north of Adelaide) on the night it was thought that Stevenson had died. Szach had originally bought a bus ticket for the journey. However, he was reimbursed for the ticket shortly before he left Adelaide, and travelled overnight to Coober Pedy in Stevenson’s rather ‘flash’ car. Police regarded this as suspicious at the time as Stevenson was said to have been possessive about his car.
Szach was questioned by the police in Coober Pedy, and later there was some confusion about the precise timing and content of these interviews. The defence argued at the trial that the police deliberately didn’t tell Szach before the interviews that he was regarded as a suspect in the murder in the hope that he might inadvertently reveal something of value to them. It is a breach of police procedures to interview a suspect without properly informing them of their real purpose. It would, for example, be unfair to Szach if he thought that he was being interviewed on a charge of car stealing, while the police were actually trying to obtain information against him on a charge of murder. The police said that the interviews had taken place before they had received phone calls from the police in Adelaide telling them of the murder.
Szach was charged with murder and tried in the Supreme Court in Adelaide, in November and December 1979.
Timing of death
Stevenson’s body was found in his freezer. The pathologist, Dr Manock, calculated the time of death by utilising a formula which had been developed from experiments where bodies had been frozen in the prone position (that is, lying flat). When Stevenson’s body was found, however, it was bent round in the foetal position with his back uppermost and his arms and feet downwards.
Dr Manock said that he used the formula to calculate the time the body took to cool, adjusting the formula by 40 per cent because Stevenson’s body was doubled over rather than prone. In those circumstances, he said, there would be a reduced surface area of the body exposed and it would therefore take longer to cool down. This is correct. The difficulty arises in how much the formula is to be modified. A modification of about 40 per cent can hardly be classified as an ‘adjustment’. In his autopsy report, Dr Manock stated:
“A body will cool 85 per cent of the temperature differential within 28 hours. However, where the effective surface area is reduced, the time is lengthened and in the above circumstances it is my opinion that the lengthening of cooling time would be about 40 per cent.”
Dr Manock did not provide any scientific basis for such an adjustment. This is an example of a fact being accepted into evidence on the basis of an assertion without any properly established evidence or studies to support it.
The ultimate effect of this evidence was to make Szach a plausible suspect because he was in the vicinity at the calculated time of death. It also meant that another ‘person of interest’ to the police an alibi.
Pathology evidence reviewed
Some years after the trial, Dr Byron Collins, a consultant forensic pathologist, reviewed the pathology evidence. In his report he said:
“Dr Manock’s formula was initially proposed by Fiddes and Patten with their work being published in the Journal of Forensic Medicine, 1958. On the review of the paper, it becomes transparently obvious that it was not applicable to the circumstances of Derrance Stevenson’s death." [3]
A basic principle of scientific work is that the procedures are capable of being replicated. This means that they can be spelled out in such a way that another scientist could go through the same procedure and arrive at the same answer. In his report, Dr Collins outlined the reasons for his view that it was not appropriate for Dr Manock to use the formula to calculate time of death in this case. He pointed out that the authors of the research report, which was based on experiments on bodies frozen on the prone position, stressed that their findings were not to be used or applied in circumstances which varied significantly from those of the experiments.
Dr Collins noted in his report that fundamental to the reliability of any formula is the accuracy of its individual factors. He went on to say that none of the variable factors that Dr Manock used in his calculations were matters that could be properly substantiated.
For example, Dr Manock substituted a liver temperature for a rectal temperature. He did not explain why he thought that one could just be substituted for the other.
The running temperature of the freezer was unknown at the time the body was placed in it. In normal mode it would have been –20 degrees C, but in superchill mode it would have been –28 degrees C – a significant difference.
The core body temperature at the time of death was assumed by Dr Manock to be 37oC, but he provided no evidence to support this assumption. In normal circumstances, bodies begin to cool down after death and Dr Manock had no way of determining the time between the shooting and when the body was placed in the freezer. Without knowing the room temperature and the length of time between death and refrigeration, Dr Manock would have had little idea of the body temperature at the time it was placed in the freezer.
Szach convicted
Szach was convicted of murder and sentenced to life imprisonment. He appealed, and this was heard in March and April 1980, but was unsuccessful. In 1991, Michael David, QC inquired into the matter on behalf of the Legal Services Commission to determine if it should fund a further appeal. He advised against it.
Throughout his time in prison Szach refused to apply for parole because he claimed that he was in jail because of the shortcomings of the legal system. He claimed throughout that he did not commit the crime and that he would not apply for parole as that would amount to an admission of guilt. Eventually the law in South Australia was changed to enable the Chair of the Parole Board to apply for a non-parole period on behalf of a prisoner. Szach was released in 1993.
Gerald Warren killed
Gerald Warren, an aboriginal youth, was having a drink on a road outside Port Augusta, South Australia, when he threw his empty beer bottle at a passing utility vehicle. Little did he suspect at the time that such a thoughtless act would lead to his death. The two men in the vehicle took offence at his action and determined to make this apparent to him. They bought some beers, came back and enticed Warren into the vehicle to join them for a drink. They drove out of town with him a short way and battered him to death.
His body was found on a dirt track on 28 December 1984. Dr Manock, who happened to be in Port Augusta that day, arrived at the scene at 10.45 pm. He noticed that the injuries Warren had on the back of a hand and his face had fine parallel lines within them. In his autopsy report dated 14 May 1985, Dr Manock said he thought that these injuries had been made by Warren’s corduroy trousers pressing against his face and hands. After examining the rest of the injuries, Dr Manock said, ‘It is my opinion that the deceased received his injuries as a result of leaving a moving vehicle’. As a result, it was not clear if the death resulted from an accident or from criminal activity.
In 1991 two men, Stefan Niewdach and Alan Ellis, were separately apprehended for various offences and they confessed to killing Warren. They explained that they had beaten Warren with a brass rod with a threaded end. Then they had driven the vehicle backwards and forwards over his body. At their trial, Dr Manock was asked to explain the discrepancy between their story and his own explanations in his autopsy report.
Dr Manock said that if Warren had been beaten with a threaded rod, or if he had had corduroy pressed against his skin, he would be left with similar injuries. He then went on to say that if Warren had fallen out of a car, or if the car had been driven over the top of him, the resulting injuries would also have been similar. The following extracts of the prosecutor’s questions to Dr Manock are taken from the trial transcript:
Prosecutor: That damage [to Warren] could possibly have been caused by the body being run over by a motor car, could it?
Dr Manock: Yes.
Prosecutor: Or it could have been caused by the body leaving a motor vehicle?
Dr Manock: Yes. The forces involved in either scenario are very similar.
In a later exchange, Dr Manock responded to defence counsel in cross-examination as follows:
Counsel: The possible cause that you gave for those marks [on the back of Warren’s hand and face] was the fabric of corduroy, wasn’t it?
Dr Manock: Yes.
Warren happened to be wearing corduroy trousers. Dr Manock said that Warren had tumbled from the vehicle and ‘the tumbling was required to bring corduroy in contact with hands, face.’ This was how the corduroy could have been ‘impressed’ against the back of his hand, or indeed his face. Counsel continued:
Counsel: I take it that’s still, in your view, a possible cause of those marks.
Dr Manock: It would certainly produce a patterned mark
Counsel: So, while you agree with my learned friend that those marks may have been caused, as she asked you to hypothesise, by the thread of a piece of iron, and you agreed that’s consistent with that.
Dr Manock: Yes.
Counsel: But also consistent, you would still say I think, with the pressure from the corduroy of the pants.
Dr Manock: Yes.
Counsel: You’d have no reason to resile from that view.
Dr Manock: Correct.
When used to inflict blunt injuries, threaded metal rods leave a characteristic pattern of abrasion on the skin, with or without a central laceration (tearing of the skin). [4] Recognising this characteristic injury may categorise the weapon and lead to its discovery. The suggestion that a blow to the face with the threaded end of a metal rod would leave the same mark as corduroy being impressed against the skin isn’t correct. Likewise, the proposition that the ‘same forces’ are involved if someone ‘leaves’ a moving vehicle, as having a vehicle driven backwards and forwards over them is also incorrect – the injuries would have been different. Being thrown out would have caused impact injuries and probably a lot of grazing; being run over would have caused crushing injuries.
Evidence of being beaten by a metal rod would strongly suggest that Warren had been seriously assaulted by another. Evidence that his corduroy trousers had been ‘impressed against his skin’ suggests he could have done that himself. The important point is that the two interpretations open up the possibility of it being either an accident or a crime. The same can be said about the deceased either falling out of the vehicle or having the vehicle driven over the top of him.
It can be seen that the arguments for injuries from corduroy and for leaving a vehicle are not consistent with the rest of the evidence as it is now known. It is important to bear in mind the way in which circumstantial evidence like this is used. If there is a rational explanation consistent with the accused’s innocence (and the evidence is circumstantial) then the court should not convict the accused. This does not mean that the two alternatives can be weighed and the court (or the jury) can decide what is thought to be most likely. So long as the two possibilities exist, then the court should not convict the accused. This was the principle stated by the South Australian Court of Criminal Appeal following the Van Beelen trial, as we saw in the previous chapter.
Other problems
An examination of the trial transcript in this case reveals a series of unscientific or unsubstantiated statements by Dr Manock.
Explanations about bruising
Dr Manock said that ‘there was nothing to indicate there had been repeated blows to the body’. This is difficult to understand. It is now known that the injuries on Warren’s hand and face were the result of blows from the metal rod, and that his body had been driven over by a vehicle at least twice, with four wheels going over his body. The injuries from the rod and the vehicle could not have been caused simultaneously.
Explanations about the placing of the body
At the trial Dr Manock said that he took the view that the body had been placed where it was found, rather than tumbled or rolled there. He also said that he had not put that in his report because he had no firm evidence to say the body had been moved. However, there was in fact no evidence for it at all.
Dr Manock said that ‘his opinion’ that the body had been placed there was based on the observation that the grass around the deceased’s leg was still standing and not flattened. He agreed, however, that the leg could have gone over the grass, rather than through it. He thought that if the leg had ‘brushed through’ the grass it would have flattened it more, because he had observed that the grass was quite brittle. Given, though, that he had just admitted that the leg could have ‘gone over’ the grass instead, his observations about the grass not being flattened were not significant or relevant and do not constitute evidence for or against anything at all.
Missed information
Dr Manock agreed that in a photograph of the deceased at the scene ‘it looked as though’ there was a wet area on the body, but he could not say what it was or how it might have got there. His evidence was that the body had been on the track on a particularly hot day and that, based on his time of death, it had been there at least from ‘noon to 4 pm’. If indeed there was a ‘wet area’ on the body, it could have been an important clue as it does not fit that situation. At the very least he should have examined it, recorded it in his report and taken samples of it for testing.
Blowfly activity
In his autopsy report, Dr Manock said that he timed the death on the fact that the body was not fly-blown. At the trial, in cross-examination by the defence counsel, he said:
Counsel: How is it then that you are able to say it was unlikely that death had occurred after 4.00 p.m. on that day?
Dr Manock: The main reason that I came to that conclusion was that the body was not fly blown extensively and I felt blow flies would be active in the early evening. I have since learned on very hot days blow flies are not active at all if temperatures are very high and will not cause fly strikes.
He said he also thought at the time that the activities of scavengers, such as crows, may have discouraged the flies. Blowflies and their activity are an important method of determining the time of a death that has occurred in the open. However, blowfly activity only becomes valuable some 48 hours after death, which was not the situation here. Within the first 48 hours, rigor mortis and lividity are usually more precise indicators.
Dr Manock had also considered the amount of bird droppings in making his estimate. On further questioning he agreed that his observations in this respect were just his ‘layman’s observations’. However, he was supposed to be giving evidence as an expert witness.
Incorrect time of death
In his report, Dr Manock said that Warren’s death had occurred between noon and 4 pm on the day he was found. It was revealed, at the trial, however, that the death had actually occurred around midnight of the previous day. When pressed about which bits of his reasoning still supported his conclusion, Dr Manock said: ‘I don’t think I was restricting the timing. That I chose to simply put a relationship for the putrefaction change until that was related to the total picture.’
It is not clear what Dr Manock may have meant by that. He seems to be saying that ‘noon to 4 pm’ was consistent with ‘not restricting the timing’. When he was asked why he hadn’t ‘widened the ambit’ he said, ‘I didn’t put any range of possibility to any great extent’. When Dr Manock had explained that the process of putrefaction would produce gas within the body, he was asked by defence counsel for more details.
Counsel: Was there any gas production within the organs?
Dr Manock: Not of any great significance, no.
Counsel: Was there any at all?
Dr Manock: No.
It appears that there was no putrefaction change to be related ‘to the total picture’. It also appears that the expression ‘not of any great significance’ was the same to Dr Manock as ‘none’.
In his autopsy report, Dr Manock fixed the time of Warren’s death with some degree of confidence. Between noon and 4 pm he claimed. Obviously this would be significant if the police were considering making criminal charges. If the death had occurred around midnight of the previous day, as was subsequently found, then the perpetrators could be somewhere else between noon and 4 pm the following day. They would then have a ‘cast-iron’ alibi in connection with the alleged murder of Warren. It would not be hard to imagine that if anyone else had chanced to be around at the scene between noon and 4 pm that day, then they might have ended up being accused of the murder.
Endnotes
1. The discussion of the Stevenson case is based on the appeal transcript, The Queen v. Szach 1980 23 SASR (in Banco) King CJ, Legoe and Mohr JJ, 504–594, Dr Manock’s autopsy report dated 27 July 1979. Also the following newspaper reports: ‘Adelaide lawyer found murdered’, The Advertiser, 6 June 1979; ‘Lawyer, miner “were lovers”’, The Advertiser, 7 August 1979; ‘Bullet wound only injury: pathologist’, The Advertiser, 9 August 1979; ‘Miner, lawyer “fell for each other quickly”’, The Advertiser, 10 August 1979; ‘Man cried for his best friend, court is told’, The Advertiser, 4 October 1979; ‘Szach guilty: life imprisonment’, The Advertiser, 20 December 1979; ‘New probe into lawyer’s murder’, Sunday Mail, 25 August 1991.
2. The discussion of the Warren case is based on the autopsy report of Dr Manock dated 14 May 1985, the transcript of R v Stefan Niewdach and Alan Ellis (1992), Dr Manock’s evidence (pp. 122-144) and the summing up of the judge presiding at the trial.
3. Report of Dr Byron Collins to AD Dudek, Barristers and Solicitors, Adelaide, 5 August 1994.
4. RE Mittleman & CV Wetli, ‘The threaded bolt injury pattern’, Journal of Forensic Sciences, no. 27 1982, pp. 567–71.
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