The challenges faced by counterterrorism authorities are numerous. They include determining whether a person jailed for terrorism-related offences – and now due for release – has been deradicalised by imprisonment, or is just faking it; determining whether persons returning from war zones, like recently returned Australian Ashley Dyball, have been illegally involved in conflict (they invariably claim to have been engaged in humanitarian work); establishing whether a person has bomb-making knowledge, and; determining whether a young Muslim trying to depart Australia has been accessing Islamic State briefing material on how to get to Syria.
One technology seems to have the potential to provide national security authorities with important indicators as to a person-of-interest's likely involvement in terrorism – and even his or her level of radicalisation. It's been labelled "brain fingerprinting" technology, though a less confronting and more marketable title for the technology might be "Memory Scanning").
What, might you ask, is brain fingerprinting?
It is a forensic science technique that uses electroencephalography (EEG) to determine whether specific information is stored in a subject's brain by measuring electrical brainwaves based on the brain's response to words, phrases or pictures presented to it on a computer screen.
The brain responds differently when exposed to information it already knows, compared with unknown information. An electrical signal is emitted from an individual's brain about 300 milliseconds after it is exposed to a recognisable stimulus. This stimulus could be the face of a terrorist recruiter, a weapon used in an attack, a training camp in Syria, a page in a bomb-making manual etc.
The theory of brain fingerprinting was developed by Dr Lawrence Farwell in the early 1990s and has been developed further since then. (Farwell was at one stage selected by Time magazine for the "Time 100" – the 100 innovators who could become the Picassos and Einsteins of the 21st century.)
Brain fingerprinting has two potential national security/law enforcement applications: detecting knowledge of a specific crime, terrorist act, or incident stored in the brain, and; detecting a specific type of knowledge, expertise or training that may be relevant to terrorism or crime.
Other potential applications of brain fingerprinting include early detection of Alzheimer's, measuring the efficacy of drugs in treating brain disorders and, more frivolously, measuring the effectiveness of advertising.
The marketer, Brainwave Science, claims a brain fingerprinting error rate of less than 1 per cent in laboratory tests and field trials conducted by the CIA, FBI and US Navy. According to Brainwave Science, independent researchers have reported a similar low error rate and high statistical confidence. In one such study, Dr Farwell and former FBI scientist Dr Drew Richardson tested the effectiveness of brain fingerprinting in detecting bomb-makers. Apparently all the bomb-makers were correctly identified.
Brain fingerprinting is very different to polygraphing, sometimes referred to as a lie detector test, which depends on the skill of the operator and sometimes has an accuracy rate not much better than even. A polygraph measures emotion-based physiological signals such as heart rate, sweating and blood pressure. It is, however, possible to defeat a polygraph test. Since 1945 at least six Americans committing espionage against the US have managed to successfully pass polygraph tests.
In the US, brain fingerprinting has reportedly been ruled admissible in court and the manufacturer claims success in two high-profile criminal cases – the JB Grinder and Terry Harrington cases.
Grinder was a suspect in the murder of Julie Hilton and two other girls but, for 15 years, there was insufficient evidence to convict him. Brain fingerprinting indicated however that Grinder had knowledge that could only be known to investigators – and the murderer. Grinder subsequently confessed and, in a plea deal, was sentenced to life in prison without parole to avoid execution.
By contrast, Terry Harrington had been convicted of murder, but brain fingerprinting showed he did not know what the murderer must have known. Harrington was released from prison based on a constitutional rights violation in the initial trial, and Iowa settled a compensation case by paying $12 million to Harrington and another defendant.
Brain fingerprinting has not yet been widely employed outside the US, although it is currently being demonstrated in Australia. There may be some official cynicism here because of past US and Israeli claims concerning the accuracy of various types of lie detection technology. When tested in Australia they did not deliver the outcomes claimed; polygraphing being a case in point.
In Australia, the High Court has yet to consider the validity of polygraph evidence, but in 1982 a district court in NSW deemed it inadmissible on several grounds – including that it was hearsay evidence. (Lie detector evidence is currently inadmissible in NSW courts under the Lie Detectors Act.) At one stage polygraph testing was trialled by ASIO for vetting purposes, but not adopted.
How then is a brain fingerprinting test conducted?
The basic tool is a laptop. A testing site takes about 10 minutes to set up and a test takes less than an hour. The subject wears a headset with electronic sensors that measure EEG emissions from several locations in the brain. The subject views carefully selected words, phrases, or pictures on a computer screen. Brain reactions are recorded for analysis.
Stimuli provided are of three types: "irrelevant" stimuli that are new to the subject (used to get a base-line); "target" stimuli that are relevant to the investigated situation and known to be known to the subject, and; "probe" stimuli that are relevant to the investigated situation that the subject claims to know nothing about.
Brainwave Science claims the FBI found brain fingerprinting had applicability in 85-90 per cent of criminal and civil cases, while fingerprinting and DNA have only 1-2 per cent applicability (The FBI has not publicly confirmed these claims).
It is unlikely that a conviction could be secured on the evidence of brain fingerprinting alone, but brain fingerprinting seems potentially to be a useful indicator to guilt or innocence in some of the circumstances mentioned.
No doubt civil libertarians will see this as another threat to a person's privacy – but testing could be based on a person's willingness to participate as a way of removing themselves from suspicion. An important issue in any future use of brain fingerprinting technology – if it proves to be as effective as claimed – is what is reasonable in terms of ensuring the safety of the public and what rights we can afford to allow a person of ongoing security concern.
Clive Williams is an adjunct professor at Macquarie University's Department for Policing, Intelligence and Counter Terrorism and a visiting professor at the ANU's Centre for Military and Security Law.
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