You want facts? This quote is from Treuhaft himself, found at this site: HERE.
So, in the next year, after the convention, '57 to '58, we had lost all of our illusions about the Party, and just felt that it was not accomplishing anything. That's why we left it, because it became more and more a waste of time. Why go to meetings and put all your energy into working for Party organizations if you were butting against a stone wall in the national leadership of the Party? And in the local leadership of the Party too, actually, after a while? So we dropped out on a fairly amicable basis. We told the county chairman here that we were leaving. We asked for a meeting with him to explain why, and he became rather angry, but a couple of friends of ours dropped out too.Of course, after the Khrushchev revelations, very large numbers of people began to leave the Party. We used to call it "defecting" from the Party at first, until we did it ourselves. And so, after '58, we still received the Party newspaper. We had won a life-time subscription, in fact. And we continued to get The People's World, which was a weekly at that time. A couple of years ago, when it was cluttering up the house and we really were rather tired of reading it; then when it became a daily, and it came too often, and it was edited more and more from the East, we wondered how we could get rid of this life-time subscription. We thought we might have to produce proof of death or something like that [laughter], in order to do it. Anyway, we did stop it. So that's the Communist party background.
Now, individually, and publicly, I never announced that I had left the Party. I never avoided red-baiting by saying, "Well, I'm not a Party member anymore." As a matter of principle, I didn't think it was a thing that needed to be publicly discussed unless it was relevant to whatever came up. And, of course, it did come up when I ran for district attorney in 1966. I was red-baited by the incumbent to some extent there.