Actori incumbit onus probandi
Latin: The burden of proof lies on the plaintiff
Also called: Burden of proof on the party who asserts
The burden of proving a fact lies on the party who asserts it and seeks judgment on it. Reflected in Sections 104 and 105 of the BSA.
Explained
Actori incumbit onus probandi means that the burden of proof rests on the actor, that is, the party who brings the claim. A plaintiff or prosecutor who asks the court to act must prove the facts on which the claim depends; the defendant need not disprove what has not been proved. The companion idea is ei incumbit probatio qui dicit, non qui negat: proof lies on the one who affirms, not on the one who denies.
The maxim is embodied in the Bharatiya Sakshya Adhiniyam, 2023. Section 104 (earlier Section 101 of the Indian Evidence Act, 1872) provides that whoever desires any court to give judgment as to any legal right or liability dependent on facts which he asserts must prove that those facts exist, and that the burden of proof then lies on him. Section 105 (earlier Section 102) gives the test: the burden in a suit or proceeding lies on the person who would fail if no evidence at all were given on either side. Section 106 (earlier Section 103) applies the same rule to any particular fact.
Two senses of 'burden' must be kept apart. The legal burden, fixed by the pleadings and Section 104, never shifts. The evidential burden, or onus, may shift during the trial as one side produces evidence that calls for an answer. The illustration to Section 105 makes this concrete: where execution of a bond is admitted but fraud is alleged, the burden of proving fraud is on the defendant, because without evidence the plaintiff would succeed.
The law departs from the maxim in defined cases. Section 108 of the BSA puts on the accused the burden of proving that his case falls within a general or special exception, Section 109 places the burden of a fact especially within a person's knowledge on him, and statutory presumptions, such as that of dowry death in Section 118 or in favour of the holder of a cheque under Section 139 of the Negotiable Instruments Act, cast the onus on the other side. Examiners test the Section 105 test and these exceptions.
What the law says
Whoever desires any Court to give judgment as to any legal right or liability dependent on the existence of facts which he asserts must prove that those facts exist, and when a person is bound to prove the existence of any fact, it is said that the burden of proof lies on that person.
Illustrations.
(a) A desires a Court to give judgment that B shall be punished for a crime which A says B has committed. A must prove that B has committed the crime.
Burden of proof lies on the party asserting facts
Earlier law: IEA 101. Burden of proof.
The burden of proof in a suit or proceeding lies on that person who would fail if no evidence at all were given on either side.
Illustrations.
(a) A sues B for land of which B is in possession, and which, as A asserts, was left to A by the will of C, B's father. If no evidence were given on either side, B would be entitled to retain his possession. Therefore, the burden of proof is on A.
Test of who would fail if no evidence were given
Earlier law: IEA 102. On whom burden of proof lies.
The burden of proof as to any particular fact lies on that person who wishes the Court to believe in its existence, unless it is provided by any law that the proof of that fact shall lie on any particular person.
Illustration.
A prosecutes B for theft, and wishes the Court to believe that B admitted the theft to C. A must prove the admission. B wishes the Court to believe that, at the time in question, he was elsewhere. He must prove it.
Burden as to a particular fact
Earlier law: IEA 103. Burden of proof as to particular fact.
When a person is accused of any offence, the burden of proving the existence of circumstances bringing the case within any of the General Exceptions in the Bharatiya Nyaya Sanhita, 2023 or within any special exception or proviso contained in any other part of the said Sanhita, or in any law defining the offence, is upon him, and the Court shall presume the absence of such circumstances.
Illustrations.
(a) A, accused of murder, alleges that, by reason of unsoundness of mind, he did not know the nature of the act. The burden of proof is on A.
Burden on accused to prove exceptions
Earlier law: IEA 105. Burden of proving that case of accused comes within exceptions.
Earlier law: Section 101, Evidence Act
Example
Illustration (a) to Section 104 of the BSA: A desires a Court to give judgment that B shall be punished for a crime which A says B has committed. A must prove that B has committed the crime.
For the exam
- Meaning: the burden of proof lies on the party who asserts the claim.
- Embodied in Section 104 BSA (earlier Section 101 IEA).
- Test: the burden lies on the party who would fail if no evidence were given (Section 105 BSA).
- Legal burden does not shift; the evidential onus may.
- Exceptions: Sections 108 and 109 BSA and statutory presumptions such as Section 118 BSA.
Related terms
- EvidenceUnder Section 2(1)(e) of the BSA, statements of witnesses before the Court, including those given electronically (oral evidence), and documents, including digital records, produced for its inspection (documentary evidence).
- FactAnything, state of things or relation of things capable of being perceived by the senses, and any mental condition of which a person is conscious (Section 2(1)(f) of the BSA).
- AlibiA defence plea that the accused was at another place when the offence was committed, so that he could not have committed it. Relevant under Section 9 of the BSA; the burden is on the accused.
- Facts in issueFacts from which, alone or with other facts, the existence, non-existence, nature or extent of a right, liability or disability asserted or denied in a suit or proceeding necessarily follows (Section 2(1)(g) of the BSA).
- Conclusive proofWhere the Adhiniyam declares one fact to be conclusive proof of another, the Court, on proof of the first, must treat the other as proved and cannot allow evidence to disprove it. Section 2(1)(b) of the BSA.
Further reading
Checked 6 November 2026. Statutory text is quoted from the Bare Acts library, taken from India Code. See the full glossary.