As someone who thought Sotomayor would be awful on civil liberties due to being a prosecutor, it's worth noting that she's been one of the best in that regard (IMO) since joining the court. On the other hand, Kagan went straight from being a government attorney to the Supreme Court, so maybe you could expect her to be more inclined to side with the government in these cases.
> Is this something that can be remedied just with normal legislation, or are we now in need of a new constitutional amendment?
Legislation can certainly curb it, though it can also be repealed and bypassed if it leaves any openings.
I might be suffering from listening to too small a sample (though they were right...), but I heard much more positive commentary about Sotomayor before she was confirmed than Kagan. It seemed like party insiders liked Kagan because she was an insider, but that was all.
> Is this something that can be remedied just with normal legislation, or are we now in need of a new constitutional amendment?
Legislation can certainly curb it, though it can also be repealed and bypassed if it leaves any openings.