Medical cannabis experts, Professor Mike Barnes and campaigner Hannah Deacon sit down with their guests to find out why cannabis matters to them.----In the final episode of the series, Hannah interviews Professor Mike Barnes for a rare insight into how he ended up as one of the UK's leading cannabis experts.Now known to many as the UK's 'cannabis doctor' Mike spent most of his career as a leading neurologist at the Royal Victoria Infirmary in Newcastle upon Tyne. He set up the World Fed...