Hair Testing in the Family Court – Resolution Podcast
Podcast highlights miscarriages of justice in hair strand testing
In the latest Resolution podcast episode, Sarah Branson (Coram Chambers) and Professor James Coulson (Cardiff University) discuss the risk of miscarriages of justice due to over-reliance on hair testing results. They highlight the racial bias in standardised cut-off levels, as darker hair with higher melanin concentrations incorporates more drugs than red or lighter coloured hair, leading to disproportionately higher readings.
Sarah advocates for hair testing to follow standard expert evidence protocols, including proper instructions and forensic history. She emphasizes that while test results are scientific data, their interpretation is expert opinion.
Professor Coulson stresses the need for comprehensive contextual evidence and explains what should be included in future instructions. Together, they urge treating hair test results as part of a broader expert analysis, not as definitive proof.
FTS supports the view that hair strand testing is expert opinion evidence, and that all findings must be fully reported and explained in toxicology reports.
References (listed below) include key studies on drug incorporation in hair and related forensic interpretations.
Reference Information
Sarah directs us to the judgment of Lord Peter Jackson in D, Re (Children: Interim Care Order: Hair Strand Testing) [2024] EWCA Civ 498 (10 May 2024) https://www.bailii.org/ew/cases/EWCA/Civ/2024/498.html. Sarah points out the numbers from a test is the science but what those numbers mean is just someone’s opinion like any other expert evidence.
During the discussion, Sarah and James refer to:
The incorporation of drugs into hair: relationship of hair color and melanin concentration to phencyclidine incorporation M H Slawson, D G Wilkins, D E Rollins J Anal Toxicol 1998 Oct 22.
The effect of hair color on the incorporation of codeine into human hair. Rollins DE, Wilkins DG, Krueger GG, Augsburger MP, Mizuno A, O’Neal C, Borges CR, Slawson MH.J Anal Toxicol. 2003 Nov-Dec;27(8):545–51. doi: 10.1093/jat/27.8.545.
Cuypers E, Flanagan RJ. The interpretation of hair analysis for drugs and drug metabolites. Clin Toxicol (Phila). 2018 Feb;56(2):90-100.