Now that Supreme Court transcripts identify justices by name, which has only been the case since October 2004, it's possible to (choose one):
[gain even more insight into the thought processes of the justices]
[waste even more time analyzing pointless statistics].
I guess those choices are not completely interchangeable, because here's one pointless statistic that won't give you insight into anyone's thought processes: Justice Thomas did not say one word during the 68 hours of oral argument during the Court's latest term. Thomas has never said very much from the bench, but he has typically thrown out at least a couple of questions each term. He has said that he will ask a pertinent question if someone else doesn't, but on the other hand doesn't need to speak just to hear his own voice.
Fair enough, although that does seem to imply that the other justices are awfully fond of their own voices, because they're asking questions. Especially Justice Breyer, who, according to the report, has uttered almost 35,000 words during oral argument just since January, while Thomas's total is 281 -- and that's since they started keeping records of this back in 2004. Justice Thomas hasn't asked a question in court since February 22, 2006. (And that was probably to ask Breyer if he ever shuts up.)
Since it's probably fair to assume that legal questions are longer than average, it is entirely possible that Justice Thomas has averaged one question during oral argument in each of the 16 years he has been on the Court. Surprisingly, the report did not quote any of these extremely rare questions, but it did allude to one question in a death-penalty case, and recalled the time when Thomas "memorably spoke up four years ago" in a pair of particularly controversial cases.
I'll try to locate and post the Thomas Questions if I'm able to find them.
(AP, May 19, 2007)