What should be our principle for a narrator if it was found that the Jarh wa Ta’deel (criticizing and praising) of him contradict each other?

All perfect praise be to Allah, The Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad is His slave and Messenger.

This is really a big issue that the scholars researched, and they greatly differed in opinion about it, and it is not possible to mention this in a fatwa.

A group of scholars determined that Ta’deel (praising a narrator) comes in priority over ambiguous Jarh (criticizing a narrator), whereas the detailed Jarh comes in priority over Ta’deel according to the view of the majority of the scholars. Some scholars favored the view of the majority. However, there are important rules that should be taken into account when researching such an issue, such as knowing the methodology of the scholar of Jarh and whether he is too strict; so the Ta’deel of a trustworthy scholar cannot be overruled by the Jarh of a scholar who is strict in Jarh. Also, one must know the methodology of the scholar of Ta’deel and whether he is lenient. So the Jarh of a trustworthy scholar cannot be overruled by the Ta’deel of a scholar who is lenient in Ta’deel, and so forth.

As for a narrator who is well-known to be trustworthy and upright and whose decent biography is well-known, then the statements of a scholar who makes Jarh on him are not taken into account.

Allah knows best.