He carried blank summons' in his brief case. If he needed info or private records he would simply issue a summons for them. He technically didn't even need to issue the Summons but some would request one for their own protection before releasing the info.
I'm not a lawyer, but it does say that they would have needed a subpeona but knew the request would get turned down.
So instead, they took the entire database of phone numbers and bank records for every customer!
All those poor, innocent, unsuspecting American citizens had all that information on a government database.
Where's the database now?