The mishna in makkos teaches that even someone who the entire Jewish people have a need for such as Yoav ben Tzrurya would have to go into exile (to a city of refuge) if he killed accidentally. I would like to know if the same law applies to a king. If a king kills accidentally does he go into exile?
Madanei Asher page 168 discusses this question and answers as follows.
Shaalos U'Tshuvis Radbaz - Volume 2 #772 says that a Jewish king is not judged and therefore would not go to exile. Regarding prior to the time of Yanai Hamelech when Jewish kings were judged he says even there a Jewish king would not be exiled based on the Gemara - Makos 10a that a Rabbi and his student would not go into exile, the same would apply by a king where he would require all his servants to go along with him, which he says is impossible.
However the Minchas Chinuch Mitzva 410:24 says that the Gemara in Makos is only talking about a Rabbi and his students, not about a king who he says would immediately lose his kingship and would have to go to exile.