The Relevance of Trauma as a 'Mental Disorder or Abnormality' in Sentencing: An Australian Case Study

Trauma is the impact of adversity on psychological, emotional, neurophysiological, physical, and social functioning and well-being. Many defendants sentenced in mainstream courts have ‘mental disorders or abnormalities’ associated with trauma. Jurisdictions such as the United States, the United Kingdom, Canada, Aotearoa New Zealand, and Australia all divert a small number of defendants from prison into secure forensic mental health facilities if they are found not guilty by reason of mental impairment. However, many more defendants with the capacity to plead or be found guilty have been found to have neurophysiological and/or psychological trauma (approximately 50% to 90%). For these defendants, how might, and how should, their trauma-related ‘mental disorders or abnormalities’ influence sentencing? This chapter examines the relevance of psychological and neurophysiological trauma in sentencing, specifically reducing moral culpability and the relevance of deterrence, and informing effective sanctions. As the Victorian Court of Appeal case of R v. Verdins is a leading Australian authority on the relevance of mental impairments in sentencing, the six Verdins principles are applied to trauma suggesting how evidence-informed sentencing that focuses on trauma as an individualised ‘mental impairment’ can lead to better sentencing outcomes for defendants across jurisdictions.