Which of the following is NOT a characteristic of the defense known as 'diminished responsibility'?

Diminished responsibility is a partial defense to murder, which means that it can reduce a murder charge to manslaughter. This defense is grounded in the premise that the defendant was suffering from a mental abnormality at the time of the offense, which impaired their ability to understand the nature of their actions or to form the necessary intent for murder.

The correct answer is that diminished responsibility is not applicable to all homicide cases, as it is specifically reserved for murder cases only. This limitation allows the legal system to differentiate between the gravitas of murder and other forms of homicide, such as manslaughter, where diminished responsibility does not apply.

Additionally, diminished responsibility can only be invoked when a defendant is able to demonstrate that a mental condition significantly influenced their actions at the time of the crime. It is, therefore, not a blanket defense applicable to all forms of homicide.

The other characteristics mentioned—specifically that it is available exclusively for murder, applies in cases of mental abnormalities, and defines a partial defense to liability—are fundamental aspects of diminished responsibility. Thus, characterizing diminished responsibility as applicable to all homicide cases is incorrect, making it the right selection for the question.