Section 43 of The Bharatiya Sakshya Adhiniyam :Opinion as to usages, tenets, etc., when relevant.

Opinion as to usages, tenets, etc., when relevant. The Bharatiya Sakshya Adhiniyam 2023
When the Court has to form an opinion as to—
(i) the usages and tenets of any body of men or family;
(ii) the constitution and governance of any religious or charitable foundation; or
(iii) the meaning of words or terms used in particular districts or by particular classes of people,
the opinions of persons having special means of knowledge thereon, are relevant facts.