Salam alaikum, in the internet you can find a lot of information that Shia Mahdi would rule his nation in accordance to the laws of Dawud (alaihi salam). Here I’d like to present you the evidence from known and well accepted shia book, that even all other Imams of Shias ruled in accordance to rules of Jews!
as-Saffar narrated in his “Basair ad-Darajat” (p 295, Published by al-Alami, Beirut, 2010):
From Himran ibn Ayun: I said to Abu Abdullah: Are you messengers? He said: No. I said: And it was reported to me by those who didn’t reach you, that you said that you are messengers! Imam asked: Who (said that?) Abul Hattab? I said: yes. Imam said, in this case he is raving (or deceiving . Narrator said: I asked: And BY WHAT DO YOU RULE? Imam said: WE RULE BY THE RULE OF FAMILY OF DAWUD!
Comments: SubhanAllah! Why so claimed Imams of Muslim nation have to rule by the rule of family of Prophet of the Jews?!!