The State of Western Australia v Lang [No 2]

The case before the court was an appeal against conviction and sentence for the accused, Lang, who was found guilty of murder and attempted murder. The accused was convicted of murdering one person and attempting to murder another in a stabbing incident. The appeal was based on the defence of insanity, with the central issue being whether the accused was mentally impaired to the extent that he lacked the capacity to know that he ought not to commit the acts, or whether his mental impairment deprived him of a relevant capacity. The appeal also considered whether the accused intentionally caused himself to become intoxicated by long term and/or recent cannabis use.

The court was required to determine whether the accused was suffering from a mental impairment that deprived him of the capacity to know that he ought not to commit the acts. The court needed to consider whether the accused's mental impairment was severe enough to constitute a disease of the mind. The court also had to assess whether the accused's impairment deprived him of the capacity to know that he ought not to commit the acts, or whether it deprived him of a relevant capacity. Additionally, the court needed to consider whether the accused had intentionally caused himself to become intoxicated by long term and/or recent cannabis use.

The court held that the accused was not suffering from a disease of the mind and therefore was not insane at the time of the offences. The court found that the accused's mental impairment did not deprive him of the capacity to know that he ought not to commit the acts, nor did it deprive him of a relevant capacity. The court also found that the accused had intentionally caused himself to become intoxicated by long term and/or recent cannabis use, which did not amount to a disease of the mind. The court dismissed the appeal and affirmed the conviction and sentence.

The court upheld the conviction and sentence of the accused, Lang, for murder and attempted murder. The appeal was dismissed, and the original findings of the lower court were affirmed.