The process of verification of the existence of illah/ effective cause (ratio legis) in an individual case, after having broadly established illah in its own whether by way of nass (main source text) or ijmaa (consensus) or deduction (istinbat).

In this sense, it refers to the application of a general rule to an individual or specific case (occurrence, event, etc).

Tahqeequl manat, (تحقيق المناط), (also spelled tahqeeq al-manat) is a branch or part of ijtihad (reasoning).