Facts bearing on expert opinions become relevant, though independently irrelevant, when they support or contradict an expert opinion that is relevant to the issue. Comparative evidence may test the reliability and evidentiary weight of expert conclusions, including evidence of symptoms in other poison-exposure cases or similar harbour conditions bearing on causation of obstruction.

Electronic evidence may be assessed through the opinion of an Examiner of Electronic Evidence where a court must form an opinion on information transmitted or stored in a computer resource or other electronic or digital form. Such opinion constitutes a relevant fact in the proceeding, and the Examiner is treated as an expert for that purpose.

Expert opinion evidence is relevant where forming an opinion requires specialised knowledge of foreign law, science, art, identity of handwriting, or finger impressions. The opinion must be given by a person specially skilled in the relevant field, who is treated as an expert. Relevant applications include medical opinions concerning poisoning or unsoundness of mind, and expert comparison of disputed writing with admitted or proved handwriting.

A party may contest a judgment, order, or decree relied upon by the adverse party where it is relevant for evidentiary purposes in proceedings. The challenge may establish that the adjudication was delivered by a court lacking competence or was procured through fraud or collusion. These grounds may be raised against its use.

Judgments, orders and decrees outside sections 40, 41 and 42 are generally irrelevant unless their existence is a fact in issue or they are independently relevant under another provision. A prior determination does not ordinarily bind different parties in later proceedings concerning libel, marital status or title to property. Its existence may be relevant where it shows motive, where a prior conviction is itself in issue, or where an earlier prosecution and conviction establish motive.

Judgments, orders and decrees concerning matters of public nature are relevant where pertinent to an enquiry, even though they fall outside the class given special effect under section 41. Their evidentiary value is not conclusive. Thus, an earlier decree involving an asserted public right of way over the same land may be considered in a subsequent trespass dispute, but cannot by itself establish the existence of that right.

Final judgments, orders or decrees of competent courts exercising probate, matrimonial, admiralty or insolvency jurisdiction are relevant where they confer, remove or declare a legal character, or declare absolute entitlement to a specific thing. Such adjudications constitute conclusive proof of the legal character or title declared, including the time at which that character accrued or ceased, or the property became vested.

Previous judgments, orders or decrees that legally prevent a court from taking cognizance of a suit or holding a trial are relevant facts. Their existence is relevant when determining whether the court ought to take cognizance of that suit or hold that trial, in relation to a legal bar against a second suit or trial.

Section 159(2)(b) permits proceedings that could have been taken against a deceased assessee to be initiated against the legal representative; it does not validate initiation against the deceased person. A scrutiny notice under section 143(2) is a substantive jurisdictional requirement for assessment under section 143(3). Where the legal representative filed the return, was registered by the Department before issue of notice, and promptly objected, a system-generated notice in the deceased person's name is void ab initio. The defect is jurisdictional, not procedural, and cannot be cured without waiver; consequential scrutiny assessment proceedings are quashed.

Section 39 applies the rule of evidentiary completeness when a statement forms part of a longer statement, conversation, document, electronic record, book, or connected correspondence. Evidence may include only the connected material that the Court considers necessary to understand the statement's nature and effect and the circumstances in which it was made. Material exceeding that necessity is excluded.

Foreign-law evidence is relevant where an opinion must be formed on the law of another country. Statements contained in books purporting to be printed or published under that country's Government authority, and reports of rulings contained in books purporting to report them, are relevant for ascertaining that law.

Statements concerning facts of public nature are relevant where a court must form an opinion on their existence, if contained in statutory recitals or specified gazette publications. Relevant sources include Acts of the United Kingdom Parliament, Central, Provincial and State Acts, Government or Crown Representative notifications in the Official Gazette, and printed papers purporting to be the London Gazette or certain Government Gazettes.

Section 36 recognises statements concerning facts in issue or relevant facts as relevant when appearing in maps or charts published for general public sale, or in maps or plans prepared under Central or State Government authority. Relevance is limited to matters customarily depicted or recorded in those materials.

An entry in a public or official book, register, record or electronic record is a relevant fact if it states a fact in issue or other relevant fact and is made in the discharge of official duty. The entry may be made by a public servant or by another person carrying out a duty specifically imposed by the law of the country where the record is maintained.

Section 34 of the Indian Evidence Act, 1872 recognises entries in regularly maintained physical or electronic books of account as relevant evidence concerning matters under judicial inquiry. However, account-book entries cannot alone establish liability. Where an entry records that a person owes a debt, it remains relevant but must be supported by other evidence before the debt or liability can be proved.

Section 33 permits prior witness evidence to prove stated facts in a subsequent proceeding or later stage where the witness is unavailable, incapable of testifying, improperly kept away, or cannot be produced without unreasonable delay or expense. Admissibility requires the same parties or representatives in interest, a prior right and opportunity for cross-examination, and substantially the same issues. Criminal trials and inquiries are treated as proceedings between the prosecutor and accused.

Written or verbal statements of relevant facts made by persons who are dead, cannot be found, are incapable of giving evidence, or cannot attend without unreasonable delay or expense are relevant only in specified categories. These include statements concerning the maker's death where its cause is in issue; records made in ordinary business or professional activity; declarations against pecuniary, proprietary, or criminal interest; pre-dispute opinions on public rights, customs, or general interests; relationship declarations made from special knowledge; family declarations in specified records; statements in instruments relating to identified transactions; and collective expressions of relevant feelings or impressions.

Admissions are not conclusive proof of matters admitted, but may operate as estoppels where applicable provisions governing estoppel are satisfied. Their evidentiary character remains non-final, although they may have binding legal consequences that prevent a party from departing from an admitted position in circumstances governed by estoppel, as legally applicable.

Section 30 of the Indian Evidence Act, 1872 permits a court, where more than one person is jointly tried for the same offence, to take into consideration a proved confession made by one accused that affects both its maker and one or more co-accused. Consideration is discretionary and may operate against the confessor as well as the implicated co-accused.

Confessions that are otherwise relevant remain legally relevant despite circumstances surrounding their procurement or making. Relevance is not displaced merely because the confession was made under a promise of secrecy, obtained through deception practised on the accused, made while the accused was drunk, or given without warning that it could be used as evidence against them.