Interesting--and colorful--column by Professor Ralph Rossum comparing Sotomayor and Souter. Rossum argues that even though their voting patterns are likely to be similar, the most notable element of Souter as Justice was his inconsequentialness:
There is every reason to believe that Sotomayor will be an equally reliable member of the liberal team. The crucial question, however, is whether the Souter seat she is assuming will remain at the end of the bench.
The question is crucial because, while Souter added "bench strength" for the liberal team, he was seldom assigned to write the majority opinion. Some statistics: Since Souter's elevation to the bench in 1990 through the end of the last court's term, the Supreme Court has handed down 1,587 decisions. Souter has written the majority opinion in only 135 of them –considerably below the average of 182 majority opinions for his other eight colleagues.
And, Souter has been given the "low hanging fruit": over 53 percent of his majority opinions have been in noncontroversial unanimous decisions. In 5-4 decisions in which Souter has been in the majority, he has been assigned the majority opinion only 22 times and 13 of those 22 have involved questions of statutory construction – less momentous than questions of constitutional interpretation. Only nine times has he been assigned the writing of the majority opinion in 5/4 constitutional decisions; just one is worthy of comment: In McCreary County v. ACLU (2005), he held for the five-member liberal majority that the Establishment Clause "mandates governmental neutrality between religion and nonreligion" and on that basis banned the posting the Ten Commandments on the wall of a county courthouse; his argument, however, was so unpersuasive that he could not keep that five-member majority together in the companion case of Van Orden v. Perry in which the court held it was constitutional for Texas to inscribe the Ten Commandments on a monument placed before its statehouse.
In other words, I think Ralph is asking whether Sotomayor will turn out to be an intellectual leader or follower on the Court. He sees Souter as an intellectual follower--an assessment that I share.
Of course, Ralph's not the only one asking that question.