That's my reading: a defense of the party impartiality of the judiciary more than any attribution to a partisan group. Of course they could still be biased say

That's my reading: a defense of the party impartiality of the judiciary more than any attribution to a partisan group. Of course they could still be biased say, in favor of those with power and capital. But since in practice, both political parties bow to capital with effectively equal deference, such a bias wouldn't surface by merely listing out which president appointed whom.