Luminol Testing of the Four Winds Dinghy in the Sue Neill-Fraser Case and the relevant Australian Standards
There has been much debate in the last week following 60 Minutes about the luminol testing of the Four Winds dinghy and the fact that the jury and Judge were led to believe that the blood of Bob Chappell was found in the dinghy. I have provided what I hope is a helpful analysis of the evidence in an earlier blog posting this week which covers relevant statements by the DPP and Judge, as well as the relevant forensic scientist.
It is interesting to understand the Australian Standards in this area of forensic science, particularly in relation to presumptive testing or preliminary screening. Luminol is one of these types of tests.
Concerningly, it appears that the luminol evidence in this case was not in accordance with:
- Australian Standard AS 5388.1 – 2012 Forensic Analysis Part 1: Recognition, Recording, Recovery, Transport and Storage of Material
- Australian Standard AS 5388.2 -2012 Forensic Analysis Part 2: Analysis and Examination of Material ;
- Australian Standard AS 5388.3 - 2013 Forensic Analysis Part 3: Interpretation; and
- Australian Standard AS 5388.4 - 2013 Forensic Analysis Part 4: Reporting.
Particular regard should be had to Part 2 page 11 and Appendix B “Presumptive and Preliminary Tests” which relates to analysis and examination of materials. Reference should also be had to AS 5388.1 or Part 1 in relation to further requirements and guidelines for the interpretation of presumptive and preliminary tests. Para 8.1.5 at page 19 states that:
Presumptive tests provide indicative results that may then benefit from further confirmatory testing. (emphasis added)
Page 41 (Appendix G) of AS 5388.1 (on recognition, recording, recovery, transport and storage of material), which is relevant to the nature of the evidence given by the forensic scientist in court in the Sue Neill-Fraser case, states:
The actual colour observed when a chemical colour test returns a positive result depends on many factors, such as the concentration of the analyte, the chemical form of the analyte (salt or free base) or the presence of interfering substances.
However, the forensic scientist in evidence in chief stated:
Yes. And when you look at those do you – are there particular strengths of the reaction that you can take note of?……Yes, what we – well we take note of several things when we spray luminol. We take note of the strength of the reaction and how long lived it is, the actual colour of the glow that you see and just the manner of the reaction itself, so whether it’s a constant glow, whether it might be sparkling or you get a bright flash which then dies down, because with experience you can distinguish sometimes between false positive reactions with luminol and true positive reactions with luminol and how it reacts, the colour, the longevity is all an indication of that. (640) (emphasis added)
Appendix B of AS 5388.1 recognises the limitations of presumptive testing and states (p.38):
For these reasons, results of presumptive tests may not be acceptable as reliable evidence in a judicial setting. They may, however, add to any later confirmatory testing, assist in planning what further testing to carry out and allow an analyst to locate latent stains as well as collect targeted samples, thus reducing unnecessary sample collection.
Presumptive and preliminary tests may be useful during an investigation for the purposes of quickly determining the potential forensic value of an item. (emphasis added)
It is clear then that follow up confirmatory testing is required in such cases.
Part 3 on Interpretation AS 5388.3 also states (at p.6):
Regardless of the specific methods or procedures used, interpretation of results shall be –
a) Based on all relevant results;
b) Supported by the data; and
c) Relevant to the forensic issues in question. (emphasis added)
In the case of Sue Neill-Fraser, as stated in an independent expert report obtained by lawyers for Sue Neill-Fraser, all confirmatory testing undertaken by FSST in relation to Bob Chappell's blood being present in the Four Winds dinghy (through the use of Hema Trace and Ouchterlony testing) was negative (16 tests from 7 different locations on the dinghy). This was not explained to the court.
It may also be relevant to consider the Code of Ethics for members of the Australian and New Zealand Forensic Science Society (ANZFSS) (see http://anzfss.org/code-of-ethics/). This is particularly the case in relation to Scientific Method, Reporting and Conduct in Court. Coincidentally, I will be attending the biennial ANZFSS conference next week in Adelaide. At the 2012 conference in Hobart, I gave a presentation to attendees on "Just How Ethical Are You?" which is available from the Presentations page of this website. I have also made submissions to ANZFSS since the Hobart conference in relation to the ethics issue for forensic scientists. ANZFSS is in the process of developing a Code of Professional Practice for Members to replace this Code of Ethics.
Although the relatively recent Australian Forensic Standards are not compulsory (and were published after the trial of Sue Neill-Fraser), they do outline accepted best practice in this area and should provide a framework to assess the value and appropriateness of forensic evidence presented to our courts. It is indeed pleasing that the forensic community have pushed for these important standards.