DNA Family Secrets: Is My Birth Father a Murderer?

Over half of adoptees in the UK eventually try to discover the identity of their birth parents. When mother of six Fi, started asking about where she came from, she was totally unprepared for the question it would raise. I was placed for adoption from birth. I didn't have any information about my biological mum and dad, until I traced what happened. When I was 20, I decided I'd quite like to trace my biological parents, and huge shock of discovering that my mother was killed. It was domestic abuse, and my father was serving time in jail, for murdering my mother. The social worker told me that when I was born, there is a statement from my father that says, he does not believe he is my father, but he was going to put his name on the birth certificate for the purposes of adoption. So, is that man who murdered my mother, is he my father or is there somebody else?