Does the Presence of a Drug in Hair Strand Testing Actually Mean Use of That Drug?

Paul Hunter, Founder of FTS, and Sarah Branson, Barrister at Coram Chambers, challenge common misconceptions about positive hair strand test (HST) results, explaining that the presence of a drug in hair does not necessarily indicate drug use. It highlights the flaws in relying solely on cut-off levels, as external contamination, previous drug use, or environmental factors can also lead to drug detection.

Their discussion emphasises the importance of expert analysis in interpreting results, rather than assuming a binary positive or negative outcome. This video also critiques the way HST results are often presented in court, warning against turning expert opinion evidence into misleading “pseudo-certainty” without considering alternative explanations.