Criminal Law
Necessity in Criminal Law
Study Necessity in Criminal Law with clear BNS rules, essential ingredients, leading cases, examples and concise exam-ready revision for law students.
Quick answer
Section 19 excuses harm likely to result from an act done without criminal intent and in good faith to prevent or avoid other harm to person or property.
Rule and essential ingredients
Section 19 excuses harm likely to result from an act done without criminal intent and in good faith to prevent or avoid other harm to person or property. Begin with the statutory language. Criminal liability follows only when the prosecution proves each required ingredient beyond reasonable doubt, subject to any applicable exception or statutory presumption.
Preventive purpose
The act must aim to prevent another harm rather than create a convenient excuse for advancing a private interest.
Good faith
The choice must reflect due care, available information and an honest assessment of the competing dangers.
Proportionate judgment
The urgency, gravity and probability of each harm matter when deciding whether the preventive choice was legally justified.
Application, limits and proof
A strong answer does not stop at a definition. It identifies the contested ingredient, compares the evidence with the statutory threshold and explains why nearby offences or defences do or do not apply.
Narrow exception
Necessity does not generally authorise intentional killing merely because the actor considers one life less valuable than others.
Alternatives matter
A safe and lawful alternative can show that causing the charged harm was not reasonably necessary.
Landmark cases
Learn the facts, the rule and why the case matters. The citation alone will not strengthen an answer.
R v. Dudley and Stephens
(1884) 14 QBD 273Held: Necessity is not a general defence to the intentional killing of an innocent person for survival.
Use in an answer: Use this authority to explain the controlling test for necessity in criminal law, then apply that test to the problem facts.
Municipal Corporation of Delhi v. Subhagwanti
AIR 1966 SC 1750Held: Reasonable precautions and the availability of alternatives remain important when harmful risk is assessed.
Use in an answer: Use this authority to explain the controlling test for necessity in criminal law, then apply that test to the problem facts.
How to write this answer in an exam
- Open with the relevant BNS provision and its purpose.
- List the ingredients in the order in which they must be proved.
- Apply conduct, circumstances and mens rea separately.
- Address the closest distinction, defence or aggravated form.
- Conclude on liability and punishment without assuming disputed facts.
Quick revision
- Section 19 excuses harm likely to result from an act done without criminal intent and in good faith to prevent or avoid other harm to person or property.
- The act must aim to prevent another harm rather than create a convenient excuse for advancing a private interest.
- The choice must reflect due care, available information and an honest assessment of the competing dangers.
- Necessity does not generally authorise intentional killing merely because the actor considers one life less valuable than others.
- The prosecution ordinarily bears the burden of proving every ingredient beyond reasonable doubt.
Test yourself
- What is the central legal test for necessity in criminal law?
- Which fact establishes the required mental element?
- What nearby rule is most likely to be confused with this topic?
Frequently asked questions
What should an answer on necessity in criminal law prove first?
Start with the charged BNS provision and the conduct it prohibits. Then prove the required circumstances and mental state separately before discussing punishment or a defence.
Are older IPC judgments still useful after BNS?
Yes, where the BNS language and principle remain materially similar. The current BNS text must lead, and an older case should not override a changed definition, ingredient or punishment.