File:Mayor Diane Feinstein Cable Car.jpeg

Diane Feinstein as Mayor of San Francisco on a cable car, between 1978-1988. From http://feinstein.senate.gov/public/index.cfm?FuseAction=AboutDianne.PhotoGallery&ImageGallery_id=e6453b4b-7e9c-9af9-7409-25342d21b627

Terms for the site are 2) Information presented on this site is considered public information and may be distributed or copied unless otherwise specified. Use of appropriate byline/photo/image credits is requested. No other specifications for the image can be found on that page.

So even though the photo itself is unlikely to be an original work of the US Federal Government (since it's not likely they go around taking publicity photos of mayors), that's the closest license I can find in the dropdown box below - it's been released to the public domain by a website run by the Federal Government, and I'm not about to question their right to do so. :-) Probably the best conclusion is that Feinstein herself owns the photo and released it this way via her Senate website.