What are the implications of "ka'Mishpat"?
Rashi: It means like the Din of an Olas ha'Of Nedavah. 1
Targum Yonasan: Like the law of the bird that was chosen to be a Chatas,, and not like a Chatas of a bull, lamb or goat. 2
Rashi writes that "ka'Mishpat" is like the law of an Olas ha'Of. This is not like either Tana in Chulin (21a-b)!
Mizrachi: The Tana'im explain like the law of Chatas Behemah (it is from Chulin money, and it is offered during the day and with the right hand.), or like the Chatas ha'Of (Melikah is done on the back of the neck). Rashi explains like the simple meaning of the verse, unlike Drashos of Chazal when they are far from the simple meaning, like he wrote in Bereishis 3:8.
Gur Aryeh: Obviously, Olas ha'Of Chovah is offered like Olas ha'Of Nedavah! There was no need to write "ka'Mishpat", therefore Chazal expounded an additional law from it.