That was certainly well-known in Berkeley and Oakland where they lived.
A deranged young man broke into my apartment on a Saturday morning in 1962 -- walked right by my husband who was helping a neighbor with a car.
I chased him out, and the entire neighborhood chased him down the block where he tried to break into another home. An elderly lady chased him out with a broom.
We corned him on the street where he was tring to walk right on the line in the sidewalk. The police came. He was armed with a razor blade and had confused me with his sister (who lived on the next corner). He threatened to kill me (his sister).
Turns out he was the son of Robert Truehaft's law partner. Who is Robert Truehaft, I asked at the time. The answer from everyone was, "The famous Communist lawyer who is married to Jessica Mitford, the sister of Hitler's lover, and author of The American Way of Death."
I'm sure that that background was not covered in the end papers of the book, but the fact was well known in Berkeley and Oakland.