adding on

Today I added two new sightings to my police force list:

1. I discovered the Government Printing Office has its own police
force. Unanswered is the question why.

2. Parked in the bowels of union station are a fleet of Amtrak police.
At least this makes some sense, although I'm not sure if train robbery
is quite as common as it was, say, 100 years ago.