Tosefta for Horayot 2:6
כָּל הַמִּצְוֹת שֶׁבַּתּוֹרָה שֶׁחַיָּבִין עַל זְדוֹנָן כָּרֵת וְעַל שִׁגְגָתָן חַטָּאת, הַיָּחִיד מֵבִיא כִשְׂבָּה וּשְׂעִירָה, וְהַנָּשִׂיא שָׂעִיר, וּמָשִׁיחַ וּבֵית דִּין מְבִיאִין פָּר. וּבַעֲבוֹדָה זָרָה, הַיָּחִיד וְהַנָּשִׂיא וְהַמָּשִׁיחַ מְבִיאִין שְׂעִירָה, וּבֵית דִּין פַּר וְשָׂעִיר, פַּר לְעוֹלָה וְשָׂעִיר לְחַטָּאת:
For all the mitzvoth in the Torah whose witting transgression is punishable by kareth and whose unwitting transgression requires a sin-offering, the individual brings a she-lamb and a she-goat; the Nassi, a he-goat, and the anointed priest and beth-din, a bullock. And, for idolatry, the individual, the Nassi and the anointed priest bring a she-goat, [it being written (Numbers 15:27): "And if one soul sin (the sin of idolatry) in error, he shall bring a she-goat," after which it is written (29): "One Torah shall there be for you for him who acts unwittingly" — all of them are equated for this offering.]; and beth-din bring a bullock and a he-goat, a bullock for a burnt-offering and a he-goat for a sin-offering.