Trevor was first elected to the Council in 1976. He has been Mayor three times, in 1982-83, 1992-93 and 2002-03. He has also been Mayor's Escort twice, in 1988-89 and 2000-01 when his wife Stella was Mayor.
Trevor chairs the Policy Committee and the Resources Panel and is also a member of the Planning and Environment Committee.
He represents the Council on the Dorchester Joint Burial Committee and the Dorchester Markets Joint Committee. He is also a member of Dorset County Council, West Dorset District Council and the Dorset Fire and Rescue Authority.