IN R. v Golds [2014] EWCA Crim 748, the Court of Appeal was asked to clarify the meaning of “substantially impaired” in the partial defence of diminished responsibility in murder cases. By virtue of s. 2(1) of the Homicide Act 1957, as amended by the Coroners and Justice Act 2009, s. 52, diminished responsibility is made out where:

1. (1) … D was suffering from an abnormality of mental functioning which –

   1. (a) arose from a recognised medical condition,

   2. (b) substantially impaired D's ability to do one or more of the things mentioned in subsection (1A), and

   3. (c) provides an explanation for D's acts and omissions in doing or being a party to the killing.

2. (1A) Those things are –

   • to understand the nature of D's conduct;

   • to form a rational judgment;

   • to exercise self-control. …

The facts in Golds were tragically redolent of many such cases. Golds suffered from schizophrenia, and was said to live in fear of “everything” and to hear voices criticising and tormenting him. His partner (Claire) had registered to become his carer. He stopped taking his medication and his condition got steadily worse. On the fateful day, according to other witnesses, there was a difficult meeting with Claire and her family, and Golds later assaulted Claire at their home. Claire told Golds to leave, and they argued further over a bank card. Golds himself did not remember what happened next, but he fetched a knife and said that he would kill Claire, which he did (22 separate knife wounds were found on her body). When the police arrived, he said that Claire “had Satan in her eyes”.