When Cairn, from Ammanford, was 17 years old he was the victim of a homophobic hate crime. Rather than focus on the negative side of things, Cairn decided to join the Police Service so that he could stop this kind of attack happening to others.
When he turned 18, he joined the Special Constabulary as a volunteer and unpaid special constable with the same powers and uniform as a regular police constable. He has also served as a special constable, special sergeant, and special inspector and more recently he was promoted to special chief officer for Dyfed-Powys Police, the highest rank possible within the Special Constabulary and, at the age of 26, is the youngest chief officer in the UK.
Cairn is a passionate advocate for lesbian, gay, bisexual and transgender (LGBT) rights. He’s a trained hate crime support officer and the deputy lead of the Dyfed Powys Police LGBT Staff Network and has also established an LGBT social and support project in Carmarthenshire to support and counsel people.
His post as special chief officer is not his only responsibility. In September 2015 he returned to education and is about to enter his 3rd year at university studying a BA in Law and Public Service. Cairn also volunteers with the RAF Cadets and the Police Cadets on weekday evenings.
In 2017, Cairn won the St David Award for Citizenship.