Hair Strand Tests can show if parents have been using drink or drugs. Such tests play can a central part in Family Court hearings every year as judges decide whether children should go into care or not. Some barristers have been raising the alarm over the way the tests are presented and interpreted in the Famly Court. And, for the first time, File on 4 Investigates talks to mothers who nearly lost their babies – thanks to hair strand tests.

Presenter: Sanchia Berg

Senior Producer: Anna MeiselProducer: Mary O'ReillyTechnical Producer: Kelly YoungProduction Co-ordinator: Tim FernleyEditor: Tara McDermott

Image: Lead Senior Scientist Dr Ellie Menzies carrying out a hair strand test