Criminal Responsibility and Insanity
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Direct answer
Section 84 of the Indian Penal Code — carried forward into the Bharatiya Nyaya Sanhita 2023 — embodies the McNaughten rules of 1843: nothing is an offence if, at the time of the act, the accused was by reason of unsoundness of mind incapable of knowing the nature of the act or that it was wrong or contrary to law. The test is cognitive and moral, applied only at the moment of the crime, and the burden of proving insanity rests on the accused. India rejected the irresistible-impulse and substantial-capacity tests, so a mentally ill person who still knew the act was wrong is criminally responsible — mental disorder alone is never a defence. Expert psychiatric evidence informs the court, but the verdict on insanity is the court's.
What you must remember
- McNaughten (IPC 84) tests: defect of reason from disease of the mind, causing incapacity to know the nature of the act, or that it is wrong, or that it is contrary to law — all judged at the time of the offence.
- Burden and standard: section 105 of the Evidence Act places the burden on the accused to prove insanity, though courts apply a preponderance standard rather than proof beyond reasonable doubt (the Shrikant Anandrao Bhosale line).
- Rejected doctrines: irresistible impulse and the substantial-capacity test of the Model Penal Code — India stays with strict McNaughten; know the contrast.
- Time of act rule: insanity before or after the offence is legally irrelevant; lucid intervals restore full responsibility; post-offence illness affects fitness to stand trial, not guilt.
- Voluntary intoxication: IPC 85 and 86 deny drunkenness as a defence, save narrowly where intoxication negatives a specific intent and was not self-induced — the exam's favourite cross-over.
- Fitness versus responsibility: competence to stand trial (understanding proceedings, instructing counsel) is distinct from responsibility at the time of the act — one may be fit to be tried yet raise section 84, or unfit yet responsible.
- Insane delusions: responsibility depends on what the delusion was — if the accused believed he was killing an attacker under a delusion, the law extends the delusion's logic within McNaughten limits.
- Outcome of a successful plea: acquittal leads to detention in a psychiatric facility during the pleasure of the state — a hospital order, not a walk free.
How the exam frames it
The theory question asks you to state and criticise McNaughten: cognitive-only, blind to volition and psychiatric nuance, yet retained for its certainty — full marks need both. The viva traps: a killing in a lucid interval — responsible? Yes. A paranoid patient kills the neighbour he believes poisons him — defence? Only if the delusion destroyed knowledge of wrongfulness. Who proves insanity? The accused, on a balance of probabilities. Finally, the Mental Healthcare Act 2017 decriminalised attempted suicide and modernised consent, but left section 84's 19th-century test untouched — a live reform debate worth mentioning.
Frequently asked questions
What does section 84 of the IPC lay down?
No act is an offence if the doer, at the time, was by reason of unsoundness of mind incapable of knowing its nature or that it was wrong or contrary to law — the McNaughten rule in statutory form.
What are the limbs of the McNaughten rules?
A defect of reason arising from disease of the mind, at the time of the act, rendering the accused incapable of knowing the nature of the act or its wrongness.
Is irresistible impulse a defence in India?
No — India adheres strictly to the cognitive McNaughten test and has not adopted the irresistible-impulse or substantial-capacity formulations.
What happens to an accused acquitted on grounds of insanity?
He is ordered to be kept in a psychiatric facility during the pleasure of the state, with periodic review — not an unconditional release.
How is fitness to stand trial different from criminal responsibility?
Fitness concerns the accused's present ability to understand proceedings and defend himself, while responsibility concerns his mental state at the moment of the offence.