What did DPP v. Courtney (1994) clarify about diminished self-control?

DPP v. Courtney (1994) clarified that diminished self-control is not the same as irresistible impulse. The distinction is vital in understanding how diminished responsibility is evaluated in cases of a crime, particularly when considering the mental state of a defendant during the commission of an offence. Diminished self-control refers to a person's inability to fully control their actions due to certain psychological or emotional factors, but it does not mean that they are completely devoid of control, as would be suggested by an irresistible impulse. Thus, the court distinguished between these two types of mental states, reinforcing that diminished self-control can be present while still recognizing some level of control over one’s actions. This ruling has implications for how defences are framed in criminal law, particularly concerning issues of mental health and culpability.