I haven’t written a blog post for a loooong time. That’s because in the last year or so I have written another book (Forensic Science and the law: a Guide for Police, Lawyers and Expert Witnesses – the first book of its kind in New Zealand) and have been involved in some high-profile cases including 18 months on the Mark Lundy case.
Now that I have surfaced again, I have read with interest two recent online stories. The first is about how great forensic science is: Fresh hope for unsolved cold cases is on its way as the DNA profile bank turns 20. The second is about repeat and prolonged failure of an aspect of forensic science (hair examination) and the FBI finally admitting it (again – fingerprints and the Madrid bombing was the previous one): I asked FBI to validate forensic hair analysis – they couldn’t.
There is no doubt that forensic DNA technology has advanced crime investigation substantially over the years. In fact, it was DNA that overturned the conviction of a man found guilty of murder on the basis that his earprint was allegedly recovered from the window of a murder victim’s house (R v Dallagher). The expert evidence at the first trial was that earprints are unique, like fingerprints. Later DNA analysis of the cellular material comprising the earprint on the window showed it belonged to someone else, which brought a dark cloud over the future use of earprints as a crime investigation tool. But on the bright side, the murder charges were eventually dropped against Mr Dallagher – after seven years in prison.
The FBI story to which I refer above relates to comparison of hairs from crime scenes with hairs from suspects or other sources. The interview is with Peter Neufeld, co-founder of the Innocence Project. The last question put to him is as follows, with his answer:
“Forensic science seems to be unravelling. Are other techniques likely to face scrutiny?
What you see with hair is illustrative of a much larger problem. A lot of the methods traditionally utilised by forensic laboratories and police departments were never validated, violating a fundamental principle of the scientific method. I think we will be seeing more of this kind of review. Ultimately, we will be better off for it.”
Forensic science has been under the microscope since 2009 when the American National Academies produced a report basically saying that all areas of forensic science, with the exception of some areas of DNA, were not up to the job. It was written with the USA in mind, but the conclusions are applicable across all jurisdictions, particularly those with adversarial criminal law systems such as New Zealand.
The courtroom is no place to test new scientific techniques: the recent Lundy retrial was a perfect example. I won’t go into that at present because of the impending appeal, but there is a lot to say about it.
The difference between these online stories is like black and white. But forensic science works in the field of grey – it should be checked and tested on every occasion.