As for the line about the U.S. Attorney...yeah, that's a hint. But probably no one will ever get it, it's pretty obscure. It will all become clear later. It's just setting up something. God...I feel like such a dork with all these "clues."
LOL, well I have no idea what that could be then, unless if the Attorney interviews him first and decides he's not suitable for the protection program for some reason. But that doesn't seem likely. *sigh*
Or maybe it's something to do with Ennis being able to find Jack? If he can't do it through the Marshal's Office, maybe he could do it via the US Attorney's somehow? If there were some information left somewhere with the FBI, or that he might know about somehow? Or if Jack had his interview with the Attorney who knew his new identity and Jack tells Ennis so he can find him later.
I need a lawyer!