John Davidson, MBE, was born in 1971 in Galashiels, Scotland. After leaving school without formal qualifications, he began working as a caretaker at the Langlee Community Centre, where he has also served as a part-time youth worker since 2002.

At sixteen, John became the subject of the BBC documentary John's Not Mad, which brought national attention to his life with Tourette syndrome. In the years since, he has become one of the UK's most recognizable advocates for Tourette awareness--speaking in schools, training police officers, running residential camps for young people with Tourette's, and offering support to families around the world. He has appeared in several follow-up documentaries, and filmmaker Kirk Jones's 2025 feature I Swear is based on his life.

John joined the board of Tourette Scotland in 2019 and was awarded an MBE the same year in recognition of "his efforts to increase understanding of the condition and helping families deal with it across the country." He continues to gain international recognition for his online advocacy and support for the global Tourette community.