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Is hair strand testing concrete evidence of excessive alcohol consumption? Kirsten Grotte discusses

There has been a recent case whereby a mother had a history of excessive alcohol abuse, which along with other issues, led to her older children being taken into care. However, an important question arose regarding the validity of hair strand testing, which was used to find out whether a parent had consumed alcohol and, if so, to what extent over a period of time: London Borough of Richmond v B and others [2010] EWHC 2903 (Fam).It is recommended that the whole judgement should be read, however I will discuss the main points that have arisen from this case.Testing for alcohol abuse not only arises in care proceedings where the Local Authority may seek to place a child in their care or supervision, but it can also exist in private law children matters in cases where a parent is seeking a residence or contact order.If, within court proceedings, a parent is alleging that the other parent is an alcoholic then hair strand testing is usually ordered. This tests for the presence and concentration of two chemicals and shows the consumption of alcohol over the whole period of time covered by the sample, in effect the length of the hair strand. For example, 3cm of hair represents 3 months worth of hair growth. The problem however is hair strand testing does not show how alcohol has been consumed within that period, including how many times over that period and how much on each occasion. Hair strand testing has also been known to show false positive results where the two chemicals have been detected over certain levels to suggest that there has been alcohol consumption in cases where the individual has not touched an alcoholic drink.This is because the chemicals can appear naturally in the body from its own metabolism or from alimentary alcohol in some foods, such as bread. It has also been warned that these tests should not be used in cases where you are testing for low alcohol use as it cannot tell the difference between total abstinence and social drinking. It has also been highlighted that people can try and reduce the level of detection of the chemicals by either using special shampoo or bleaching their hair.Therefore these type of tests may only be useful to show frequent excessive consumption of alcohol over a period of time and if you want to prove whether someone is still drinking, however maybe not excessively, then urine samples may be the best method of testing. Urine samples test for the presence of ethanol and hence provide a more direct test, but are limited due to the length of time ethanol remains in the urine.Overall hair strand testing can still be a useful tool in both public and private law children proceedings and the guidance in this particular case should be followed. New forms of testing no doubt will appear in the future as this is still an evolving science, however it is important that expert evidence is obtained and that hair tests should only form part of the overall evidence and should be used in context with other evidence and not solely relied upon.

By Kirsten Grotte