Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answer updated 4 months ago

There is a full field of knowledge called E'lm Al-Rijaal which deals with every narrator and searching and assessing his authenticity. Deviat persons are known by our scholars of E'lm Al-Rijaal and their narrations are never accepted.

Famous  Shia books on E'lm Al-Rijaal are like Kitab Al-Rijaal  by Al-Najaashi (450 Hijri),

Rijaal Al-Kashshi (350 Hijri) ,

and  Al-Fahrist by Al-Shaikh Al-Tousi  (460 Hijri) , 

Ma'aalim Al-Ulama' by Ibn Sharashoob 588 hijri.

Khulasat Al Awwal by Al-Allama Al-Hilli  726 hujri.

Tanqeeh Al-Maqaal by Al-Mamaqani 1351 hujri.

and Mu'jam Rijaal Al-Hadeeth by Al-Khoei 1413 hijri.

We only accept narrations from authentic narrators who were always in the right path.

Wassalam.