This article examines case law and legislation in order to address the question as to whether psychiatrists owe a duty of care to members of the public to detain individuals with mental illnesses and who are at risk of harming others. It explores a hypothetical scenario in which a victim, or his or her estate or family, wishes to sue a psychiatrist for negligent failure to detain an individual with a mental illness who has harmed that victim in some way. The article suggests that current law indicates that a duty of care does not exist to unidentifiable third parties and, further, there are sound policy reasons why the law should take a cautious approach to imposing a duty to detain on psychiatrists in such circumstances.