On Friday a judgment was handed down by The Honourable Mr Justice Moylan in the High Court in which he carefully analysed the evidential value of hair-strand testing for alcohol. “While hair analysis for the use of drugs other than alcohol has been used for many years, hair testing specifically for alcohol use is a relatively recent and developing science, at least in the field of forensic toxicology,” he said. “It is clearly particularly important when new scientific tests are being used for forensic purposes that they have a sound basis which makes it appropriate for the results to be used in court proceedings and which is sufficiently explained so that the court and the parties have a full understanding of the evidential basis both of the tests themselves and of any opinions based on the interpretation of the results of such tests.”
The tests have been designed to establish a pattern of drinking over a period of time but are not conclusive because ethanol is present in all hair, even that of teetotallers. Indeed traces can be the product of the environment, or the body’s metabolism and can result therefore from certain foods and cosmetics.
All of which reminds me of a case I was involved in once upon a time when Mrs Hardened Drinker’s contact with her children was severely limited because of allegations that they were at risk in her care. Hair strand testing was suggested by her husband’s lawyer as a means of satisfying both her husband and the court that, contrary to his client’s assertions that she even kept a stash of beer and brandy in the bathroom cabinet, she was not an alcoholic. Mrs Hardened Drinker was keen to prove her innocence and readily admitted the store of alcohol in the bathroom claiming not that it was medicinal, but that she used it to wash her hair. I have to admit that whilst she had a tendency to sway and slur her words when she came to see me, her hair was always glossy.
Inevitably hair-strand testing was deemed unlikely to be conclusive in the circumstances and much to Mrs HD’s chagrin she was asked to take a series of blood and urine tests instead. When the results were known, she was again able to explain them with reference to her bathing techniques. Apparently she didn’t just wash her hair in an alcoholic cocktail, but was accustomed to filling the bath with the beer and liquor before lying back to gloss her hair and occasionally and accidentally swallowing some of the alcohol that surrounded her. It was unfortunately clear from the results of those tests that she must have been taking more than the odd sly sip.