Testimony is a means of proving claims in the Islamic legal system. A fundamental question is whether a witness’s moral uprightness (ʿadālah) is required only when testimony is given or must persist until judgment. This study examines the temporal scope of this requirement based on authoritative sources of Imāmī jurisprudence, emphasizing social welfare and judicial security through a descriptive-analytical method.

The majority of jurists maintain that uprightness at the time of testimony suffices, relying on relevant evidentiary texts, narrations, analogy with subsequent insanity or death, and the principle that derived terms refer to the time of testimony. Conversely, other jurists consider subsequent moral corruption an impediment to judgment, citing the unrestricted scope of evidence supporting bayyinah, analogy with derivative testimony and withdrawal of testimony, and distinctions between subsequent moral corruption and other contingencies.

The findings indicate that, in cases involving private rights (ḥuqūq al-nās), if moral corruption arises shortly after testimony but before judgment, strong circumstantial evidence may indicate that the witness lacked the requisite uprightness when testifying; therefore, judgment is impermissible. Regarding exclusively divine rights (ḥuqūq Allāh al-maḥḍ), the rule of darʾ, which averts punishment in cases of doubt, likewise precludes judgment based on a morally corrupt witness’s testimony.

A balanced approach should distinguish between the nature of the right involved, temporal evidence, and social and judicial consequences, protecting social welfare while safeguarding judicial security against the unjustified reversal of judgments.