Diminished Responsibility (DR)

Diminished Responsibility (DR) is a partial defence to murder under the Homicide Act 1957, which allows for a conviction of manslaughter instead of murder if certain conditions are met. The defence is specifically applicable to cases of murder and provides an avenue for defendants who suffer from a recognised medical condition that impairs their mental faculties.

Legal Framework

Homicide Act 1957, Section 2:

To successfully plead diminished responsibility, the defendant (D) must prove the following elements:

1. Recognised Medical Condition:

◦ D must have been suffering from a condition recognised as a medical or psychological disorder. This includes mental illness, severe depression, or other significant mental health issues.

2. Substantial Impairment:

◦ The medical condition must have substantially impaired D’s ability to:

▪ Understand the Nature of Their Conduct: D must have had difficulty comprehending the nature or quality of their actions at the time of the killing.

▪ Form a Rational Judgment: D must have struggled to make rational decisions or judgments regarding their actions.

▪ Exercise Self-Control: D must have had a reduced capacity to control their actions or impulses.

3. Provides an Explanation:

◦ The impairment must provide an explanation for D’s actions in the killing. It must be shown that the condition played a significant role in D’s actions leading to the killing.

Case Law

• R v Brennan [2014]:

◦ Facts: D was convicted of murder after killing V. Evidence was presented showing D had severe mental illnesses.

◦ Decision: The conviction of murder was quashed, and a conviction of manslaughter was substituted. The case demonstrated that a severe mental illness that substantially impairs a defendant’s mental functioning can lead to a successful plea of diminished responsibility.

• R v Challen [2019]:

◦ Facts: D was in an abusive relationship where she was controlled by her partner. Under significant psychological pressure and manipulation, D struck her partner with a hammer, resulting in his death. She was initially convicted of murder.

◦ Decision: The conviction was revisited and, following a campaign led by Justice for Women, new evidence was considered. The plea of diminished responsibility was successfully argued due to the substantial impact of the abusive relationship on her mental state.

Justice for Women (2017)

• Role: Justice for Women is an organisation that has worked to ensure that cases involving women who have killed in situations of domestic abuse are reviewed with appropriate consideration for diminished responsibility. They focus on cases where new evidence or considerations about the defendant’s mental state can lead to a re-evaluation of the conviction.

• Impact: The work of Justice for Women has led to successful pleas of diminished responsibility in cases where new evidence demonstrated that the defendant’s actions were significantly influenced by a mental condition resulting from severe and prolonged abuse.

Summary

Diminished Responsibility allows for a murder conviction to be reduced to manslaughter if the defendant was suffering from a recognised mental disorder that substantially impaired their ability to understand, judge, or control their actions. This partial defence ensures that those who commit acts of murder due to significant mental health issues are not automatically subjected to a mandatory life sentence but are instead given a sentence that reflects their impaired mental state at the time of the offence.