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dimanche 22 avril 2012

Désastreuse détermination de l'âge osseux...

The UK Border Agency will start x-raying children again from 29 March 2012 in order to determine their age. This practice is highly controversial. The letter announcing the resumption of this procedure can be found here. This brings to mind another example of the application of false quasi-scientific ‘certainty’ to another unmeasurable: measuring skulls to determine race.
The former Childrens’ Commissioner for England, Sir Al Aynsley-Green, is on the record deprecating x-ray age assessments and since 1999 the Royal College of Radiologists position has been that x-rays are inherently intrusive, carry a degree of risk, raise the question of informed consent and that there is no normative data outside western Europe and North America.
The doctor promoting dental age assessments and engaged by the Border Agency for their pilot project, Professor Graham Roberts, draws a parallel in his own defence with similar procedures in a legal context for decisions about liability and the quantum of damages “where there is no direct clinical benefit to the subject, although there is usually a financial benefit”. The comparison is flawed, as the age assessment procedure proposed by the UK Border Agency is not voluntarily initiated or requested by the child, or even by social services, but by the UK Border Agency. This is not a case where an adult voluntarily approaches the court or legal system for their own restitution or gain and properly and voluntarily consents to examination. It involves a Government agency accusing a child or young person of lying then proposing that he or she is examined by doctors and subjected to a medical procedure.
Not only is exposing a child to ionising radiation for no therapeutic purpose arguably unethical, it is also inherently unreliable. Professor Roberts’ experience of dealing with non Caucasians is unknown but this 2009 Freedom of Information request seems to suggest he has little such experience. As recently as January this year he himself recorded that his dataset consisted of 2,700 cases of UK Caucasians and 850 ‘Afro-Trinidadian subjects’.
Professor Graham himself suggests that his procedure is inaccurate between 32 and 35% of the time. During a hearing by the Australian Human Rights Commission into the usefulness or otherwise of dental age assessments it was suggested that Professor Roberts gets it wrong 39% of the time. A number of detailed criticisms were made of his methods.
Professor Roberts himself defends his accuracy as being ‘well above the 50% threshold’, presumably a reference to the legal standard of proof of the balance of probabilities. This misunderstands the nature of the standard of proof, though. Judges and lawyers would not like to think that the outcome of a court case is always wrong in 49% of all cases, which would be the statistical reality if the balance of probabilities were interpreted in statistical terms. Rather, the threshold in each individual case is the balance of probabilities, but in many or most cases the evidence will point very much more firmly in one direction than another. This is not the case with dental age assessments, where it is absolutely guaranteed that between 32% and 39% of all decisions made on that basis alone will be wrong.
This is no basis for accusing any child of lying, never mind depriving them of the educational, welfare and support arrangements to which they would otherwise be entitled. It is not the first time, though, that the UK Border Agency has dabbled with dubious scientific processes in their Quixotic quest for certainty. The ominous sounding Human Provenance Project, linguistic analysis and, further back, virginity testing spring immediately to mind.
Immigration Law Practitioners Association members may be interested to see their resource page has further information and references.