Thanks for all the links!  Alas, after working a couple years (actually interacting with people/not being shut in) I've come to realize the world is not as by the book as I had imagined; you can get away with a lot, and even then, most people will bend the rules if you ask nicely and smile.  So after reading Romulus' advice, I called up the 
Houston Police Department's Bush International division.  They basically told me all I had to do was give them a few pieces of info so they knew to look for me.  That's it.  Mighty simple if you ask me. 

So I guess I'll be off on a jolly day of photography in downtown Houston & KIAH. 

PS: It's an old photo, I'm (semi-)clean shaven now.  Alas, employer like the clean-shaven. :-/