Forensic evidence under the microscope – looks sick

Andrew L. Urban.

Within a single week in October this year (2019), the quality of forensic evidence tendered in criminal trials across Australia came under the microscope of public attention – and was found to be infected with the disease of unreliability. 

On October 10, Liam Mannix of The Age reported that Victoria’s Attorney General, Jill Hennesy, is calling for “an immediate national review of forensic evidence over fear flawed police forensics may be putting innocent people in jail.” The subject will be on the agenda at the national Council of Attorneys-General meeting in November. The call for an inquiry comes after The Age revealed senior legal figures including Chris Maxwell, president of the Victorian Court of Appeal, had lost confidence in the accuracy of forensic science.

The review should consider the accuracy of forensic evidence and the laws that govern how it is presented in court, she said. “I’ve also called for the establishment of a working group to consider these important issues – because we need a national approach to ensure science and technology to prove guilt or innocence is used reliably and fairly,” Hennessy said in a statement.

Hennessy’s call for a review was backed by Victoria Police and the Criminal Bar Association. “We continue to be concerned about forensic evidence in court. The risk of miscarriages of justice is always present when the science is doubtful,” said Daniel Gurvich, QC, chair of the bar association.

A couple of weeks earlier, Justice Maxwell said that there was little proof that forensic techniques including gunshot analysis, footprint analysis, hair comparison and bite mark comparison could reliably identify criminals. He called on governments around Australia to urgently change the law, so that judges had to consider the reliability of forensic evidence before it was shown to juries.

Daniel Gurvich, QC, chair of the Criminal Bar Association of Victoria, said the Victorian government should now establish an inquiry into the accuracy of forensic science, calling it “a matter of great concern in the administration of justice”.

“We do agree with the president’s fears that unreliable forensic evidence is being admitted into evidence in trials,” he said. “We think unreliable forensic evidence should not get to the jury in the first place. And the danger of juries being misled, or deferring to an expert opinion, is significant.“We consider that urgent legislative change is required.” Two critical American reports, published in 2009 and 2016, led to major changes to the US and British legal systems. Not so in Australia.

“When I learnt about those reports … I was shocked,” Justice Maxwell said.

“With the exception of DNA, no other area of forensic science has been shown to be able reliably to connect a particular sample with a particular crime scene or perpetrator.

“I was asking myself, ‘Why are we not having appeals based on questions of admissibility of forensic evidence?’”

Indeed; Justice Maxwell would no doubt be shocked by the Tasmanian example of the Sue Neill-Fraser case, in which forensic evidence was presented to the jury despite being inadmissible (a further appeal against her conviction is pending):

Testimony of forensic scientist – inadmissible:
Luminol test results (described at trial as a ‘preliminary screening test’) should never be admitted in evidence in criminal trials without confirmatory follow-up tests which identify the substance involved. That did not happen here. There were actually confirmatory tests done in relation to the dinghy by way of ouchterlony tests but these were all negative.

This error was partly the cause of the overturning of the wrongful convictions in the cases of the IRA bombers in the UK and of Lindy Chamberlain in Australia.

At various times the witness said that it was possible for her to distinguish between a positive response (to human blood) and a false positive response (to other substances) by the quality of the glow or sparkle, and the duration of the glow. At other times she said that she could make such discriminations on the basis of her “experience”. These were the type of explanations which have been rejected in numerous previous cases. They do not accord with basic principles of scientific method. If they were reliable, then there would be “glow” and “sparkle” charts so that others could learn the technique and it would be published in scientific journals. And of course it would convert a ‘preliminary screening test’ into a ‘confirmatory test’.

Testimony of forensic pathologist – inadmissible:
This expert was asked to provide an expert opinion to the jury as to whether an older person, perhaps a bit frail, could be killed by a blow to the head with a wrench. This evidence was inadmissible for two reasons:

1. An expert can only give expert opinion evidence where the jury requires such knowledge to help them interpret the evidence which they have heard. An expert is not allowed to give such an opinion where the jury would already know such things from their own experience. For example, an expert is not allowed to give an expert opinion about what happens to a person after having consumed some alcohol – the jurors would know that it makes you drunk and they do not need an expert to tell them that. Clearly jurors would know that a single punch to the head can kill so that it follows that a single blow to the head with a heavy metal wrench could also kill.
2. An expert is only allowed to give an opinion where it assists the jury to interpret evidence which has been or will be led in evidence. There must be a factual basis in the evidence which relates to the opinion which is being given. In this case, there was none. There was no evidence of any body with injuries and no evidence that anyone had been hit with a wrench. Therefore, the opinion amounted to “speculation” which recent Court of Appeal judgments have stated to be clearly inadmissible.

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On October 14, the ACT Supreme Court awarded David Eastman over $7 million in compensation after Eastman had spent almost 19 years behind bars for the 1989 shooting of federal police assistant commissioner Colin Winchester — the highest ranking police officer ever to be assassinated in Australia. The 74-year-old was found not guilty at a retrial in November 2018 after an inquiry recommended his conviction be quashed due to flaws in the evidence. Police and prosecutors had relied on forensic expert, Robert Barnes, whose evidence turned out to be wrong. The Court, as part of its compensation judgement, stated that his evidence so undermined the trial “that no conviction could possibly be based upon it.” (This was based on the report of the second inquiry into this case conducted by Brian Martin, a former chief justice of the Northern Territory.)

The total cost to the ACT taxpayer of the Eastman case is estimated to be around $20 million. Wrongful convictions are expensive.

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On October 16, Dr Jason Chin of Sydney University Law School gave a presentation at Sydney’s Sussex Hotel on the desirability of using open science to improve the quality of forensic evidence put before courts, titled Can we put an end to wrongful convictions?

Brief extracts:

* There is well-established imbalance in the state’s ability to develop a forensic scientific case against an accused and the accused’s ability to assess that case and amass his or her own evidence. This inequity is heightened when the foundational science behind the state’s case was conducted opaquely and published in paywalled journals (and then applied in crime labs, which have been described as ‘organizational black boxes’). Similarly, commentators have studied access to justice in terms of legal assistance and access to databases of legal decisions. However, the factual basis of access to justice has largely been neglected. This is unfortunate because if the science behind a case was transparently reported and more affordable to assess, impecunious parties may stand a better chance at mounting a defence.

* Forensic scientists have historically been associated with the police and prosecution, making it difficult for the criminally accused to find an independent expert, let alone pay for one.

* Perhaps not surprisingly, the widespread admission of untested, invalid, or misleading forensic evidence has contributed to several wrongful convictions. Many of these convictions came to light due to the rise of DNA analysis, one of the few forensic sciences to emerge from the mainstream sciences and withstand thorough validation testing.

* Acknowledgement of these wrongful convictions inspired a great deal of research, but none was as momentous as a 2009 report drafted by a National Research Council committee of the National Academy of Sciences (the ‘NAS Report’). The report, confirming longstanding worries, catalogued a host of problems:

> deficient training and education among forensic scientists;
> lack of peer-reviewed and published foundational research establishing the validity of forensic methods;
> lack of protocols to minimize cognitive bias;
> insufficient standards for reporting findings and giving testimony; and
> scarce funding to support improvements to any of the foregoing.

* The direct impetus for many of the reforms going on in science was a crisis of confidence: opaquely conducted science was producing results that could not be reproduced.

A similar crisis of confidence may be engulfing forensic science. Attentive researchers have long noted the surprising frequency at which forensic science has committed factual mistakes. Media attention and subsequent popular knowledge seems to be catching up with this academic research. When law—a field inextricably tied to forensic science—has sought to improve confidence in its product, the answer has often been through open justice: opening courtrooms, permitting media scrutiny, and publishing decisions. It may be time that forensic science follows suit.

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Just a month earlier, on September 10, 2019, we published extracts from a peer reviewed paper by Chris Brook in the Australian Journal of Forensic Sciences, which examines the case of Joby Rowe and finds a man was put in jail based on junk science, not scientific evidence. Brook asks: “Should forensic ‘science’ be required to actually have a scientific basis? Should scientific ‘reliability’ be explicitly required within the Australian legal system? Or should it simply follow a model of appealing to authority, allowing well qualified forensic experts to provide opinions that lack sufficient evidentiary basis?”