Gordon Campbell-Thomas, 71, of Ascot Way, York, pleaded not guilty at York Crown Court to the rape of a woman over the age of 16 and administering a substance with the intent to overpower or stupefy in order to allow sexual activity.
Mr Campbell-Thomas denies the offences, which are alleged to have taken place in 2020, and will stand trial next year.
He has previously stood in City of York Council elections, but did not gain a seat. He resigned his membership of the Labour Party in 2003 and later stood as an Independent candidate in the Hull Road ward.
Mr Campbell-Thomas was one of the founders of the St Nicholas Fields nature reserve in York and was a trustee of the John Lally International Foundation, the charity which manages it, until he retired in May 2020.
He also chaired the York Equal Access Campaign and the Hungate Community Development Trust.