In this scenario Jack could raise the defence of diminished responsibility This is defined by s.2 of the homicide act 1957(as amended by S.52 coroners and justice act 2009) as a person who kills or is party to the killing of another is not to be convicted of murder if they are suffering from an abnormality of mental functioning. This has to arise from a recognised medical condition, have substantially impaired the defendants’ ability to understand the nature of their conduct, to form a rational judgement or exercise self-control. This defence is raised by the defence on the balance of probabilities.
The first aspect of this defence is an abnormality of mental functioning arising from a recognised medical condition. This is where the working of the defendants mind was so different from that of an ordinary person that the reasonable person would consider it abnormal such as in Seers (1985). It must be a medical condition which is recognised by medical professionals. Jack was prescribed anti-depressants by his doctor who was a medical professional so was therefore suffering from a recognised medical mental illness- in this case depression so Jack is suffering an abnormality of mental functioning.
The second aspect of the defence is substantial impairment of the defendants’ ability to form a rational judgement, understand the nature of their conduct or to exercise self-control. Jack’s ability to form a rational judgement was impaired as he was overcome with emotion. The case of Lloyd states that substantial does not mean total, nor does it mean minimal but instead somewhere in between. In jack’s case this means it is sufficient as Jack’s impairment is not total but is more than minimum.
Lastly the abnormality of mental provides and explanation for the defendants act this means that there must be a causal connection between the defendants abnormality of mental functioning and the killing. The abnormality of mental functioning need not be the only factor that caused...