Where an offender suffering from a mental disorder acts with knowledge of the nature and gravity of the criminal conduct and knows that what they are doing is wrong, the mental disorder diminishes moral culpability only to a limited extent, and general deterrence retains a role in sentencing, sensibly moderated. The question of how mental illness influences the sentencing outcome is a product of its symptoms and consequences and the bearing those have on achieving the purposes of punishment; critical to the task is an evidence-based link between the illness and the purposes of punishment or mode of punishment under consideration.
The full text is available to signed-in members, including the 2 later cases that cite this judgment.
2 of the 2 citing cases carry a classified treatment. How each court treated it is available to signed-in members.