Rashi in Chumash specifically cites the Sifri, which clearly maintains that the Parshah of the judges could not possibly have taken place before Yom Kippur, even assuming that Yisro arrived before Matan Torah. According to Rashi's understanding, the Gemara clearly maintains (a) that Yisro arrived at Har Sinai before Matan Torah, and (b) that the Parshah of the judges took place before Matan Torah as well. (How, though, does the Gemara answer the Sifri's proofs? Refer to note 2 below.) In any event, the contradiction is not in Rashi, but between the Sifri and the Gemara in Sanhedrin.

b'Virchas Kol Tuv,

Eliezer Chrysler

1. Incidentally, the question arises: how does the Gemara (i.e. Rashi) derive 23 judges from Yisro, if Yisro only introduced judges of 10, 50, 100, and 1000, but not 23?

2. I found that the Aruch la'Ner questions the Gemara from the Sifri quoted by Rashi in the Chumash, as I mentioned earlier.

3. The Chidushei ha'Ran, in explaining the Gemara's Hekesh of Behemah to Adam, says nothing about Yisro. He merely says that due to the severity involved with the death of a person, it is obvious that the Beis Din consisted of 23, and the question is whether or not we learn Behemah there from Adam. It seems that the Chidushei ha'Ran means that due to the Chashivus of human life, it is obvious that Hash-m must have informed Moshe Rabeinu, already then, to appoint Batei Dinim of 23 (even though this law had not yet been specifically stated). The question of the Gemara is whether we can take the Hekesh for granted, too, or whether the comparison of animal to man only came later.