In Devarim 17:20, Rashi says that if a king is not righteous he won’t have a long reign. I’m trying to understand his comments.
Did the Sanhedrin have the right to depose wicked kings? If so, why did they not depose Yerovam, Achav and Menashe and Yehoyakim (among others)?
Sanhedrin are not the ones who choose or elected the kings. The kingship was either divinely given, through inheritance, or acquired by conquest. I would assume that if Sanhedrin would have been able to dispose of some of the wicked kings they would have done so.