No matter who originally appointed them federal judges, all members of the FISA court were appointed to that court by Chief Justice Rehnquist.
I know that Rehnquist posted them to the FISA court, but I wonder what his criteria is supposed to be. There may be very strict guidelines and, to be fair to Rehnquist, it wasn't until 2003 that you could even detect a whiff of politics in its decisions.