What are the defences to murder?

There are different defences to the crime of murder, each resulting in different outcomes. For example, there are the partial defences to murder: diminished responsibility, which exists under s.2 Homicide Act 1957 as amended by s.52 of the Coroners and Justice Act 2009; and Loss of Self-Control existing under s.54 of the Coroners and Justice Act 2009. Without going into the details of these defences in this short answer, the effect of successfully pleading these defences results in the defendant being convicted of voluntary manslaughter, which is not as rigid in its setencing as opposed to murder. There are other defences to murder, such as self-defence. If self-defence is successful, this would mean the defendant is not convicted of any crime and may walk free. (I am not sure how much detail you want in this answer, but can go into more detail during the interview.)