I revisited Mark A. Viera’s wonderful book Sin in Soft Focus. He elaborates on the production of Letty Lynton, although not without some judgement too (the murder “was excused by a woman’s need to defend her honour, even if she had tossed it overboard many reels earlier”). Apparently, in the lead-up, Jason Joy warned MGM that their script was too similar to Barnes and Sheldon’s play: “The woman in both has affairs because of the sex urge, not out of love.” It violated the Code in its philosophy. Such an approach to philosophy, says Viera, “made money, so Thalberg persisted.”
Apparently British censors didn’t pass the film because it “justified homicide without penalty.” In America, it was both despised for its lack of morals and lapped up for its honesty and support of equality. And now, we love it.