I recently stumbled upon the National Photo Company Collection in the Prints and Photographs Division of the Library of Congress. According to the Division, the collection "documents virtually all aspects of Washington, D.C., life during the administrations of Presidents Wilson, Harding, Coolidge, and Hoover." A sampler is here.
I was impressed by the number of pictures of U.S. Supreme Court justices that a search on the word "justice" turned up. (The same search brought up shots of Chief Justice with the judges of the federal judicial conference.)
For you fans of the Four Horsemen, here's Pierce Butler:
and James McReynolds:
and George Sutherland:
and Willis Van Devanter:
A search on "court" turned up a rare view of an immigration court within the Department of Labor in 1926:
Well worth a browse, IMHO.