A few years ago I visited the Louvre until closing time, and was exiting to go to the Metro (at the end of the concourse of shops). There was some special function (event) taking place, as people in
formal dress were beginning to arrive (I would assume many were dignitaries), but I saw NO police--wouldn't they be there for security? [It is possible the police were hidden away.
]
i have been to hundreds of events at museums and such in the DC area. the only uniformed personel i have ever seen are the guards at the doors of the smithsonian complex events who fish through purses. they stick some kind of a wand in them. there are always museum staff present to safeguard every room, but those are frequently female students in standard dress. most attendees are major donors, or gratis employees from major donor or sponsoring companies.