"Wer sind wir, dass wir über seinen Tisch verfügen könnten?"
Not sure, but Christian linked to this from another translation that seems to be relevant: http://german.about.com/library/weekly/aa032299.htm
Thank you for the link. That does seem to confirm "could." I was pretty sure, but it seems like when I am most certain is when I am completely wrong. Just like in real life. ;-)