Michael Cowan investigates the consequences for victims of crime and those accused of offences when crucial evidence goes missing or is lost by police forces. He speaks to a man who says he is trying to clear his name but vital evidence has been lost. Reporter: Michael Cowan Producer: Jim Booth Editor: Nicola Addyman Additional research: Wil Crisp and Sophie Eastaugh If you have been affected by sexual abuse or violence, help and support is available via the BBC Action Line. https://www.bbc.co.uk/programmes/articles/22VVM5LPrf3pjYdKqctmMXn/information-and-support-sexual-abuse-and-violence