John Davidson MBE was born in 1971 in Galashiels. After leaving school without qualifications, he began work as a caretaker at Langlee Community Centre in Galashiels, where since 2002 he has also been a part-time youth worker.
Aged sixteen, John was the subject of a BBC documentary, John's Not Mad, about living with Tourette's syndrome, and he has since been an ambassador for the condition, giving talks and workshops in schools and to the police, and running residential camps for young people with Tourette's. Since 1989 he has featured in several follow-up documentaries; Kirk Jones's 2025 film I Swear is based on John's life.
In 2019 John joined the board of Tourette Scotland and was awarded an MBE in recognition of 'his efforts to increase understanding of the condition and helping families deal with it across the country'. He has also gained international recognition for his online support for families all over the world.