Can a judge rule based on personal knowledge regarding the credibility (Jarh wa Ta'dil) of witnesses?

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The judge must rule based on personal knowledge concerning the integrity and discrediting (*Jarh wa Ta'dil*) of witnesses without dispute. If a judge were prohibited from using personal knowledge in this area, it would lead to an infinite regress (*tasalsul*). This is because establishing the credibility of the initial witnesses would require a second set of credible witnesses to vouch for them, and the second set would require a third, and so on. The current matter is distinct from general litigation because applying personal knowledge here avoids this infinite chain.