I haven't written about it much, but I'm quite the fan of film noir. In fact, my "bleeding" essay on Blade Runner goes into a lot of detail on the topic, so if you want to take a look, go ahead, I'll be here when you get back.
Over the weekend I watched Possessed, starring Joan Crawford. It's billed as film noir, but I don't think it makes the cut. Traditionally, films in the genre are about bad people doing bad things to other bad people. They're really morality tales but filled with all sorts of sordid (for the era) dealings. For example, Miles Archer - the doomed partner of Sam Spade in The Maltese Falcon - is quite the heel. His wife cheated on him, and he seems eager to return the favor.
That his death is mourned by anyone (including his wife) speaks volumes.
Similarly, William Holden's character in Sunset Boulevard is sympathetic, but also something of an exploitative heel. He plays a very cruel and dangerous game with the obviously unstable Gloria Swanson, and he's the first to admit he had it coming.
In Possessed, there's no clear line that gets crossed. Crawford is what Bugs Bunny used to call a "mental case" in every sense of the word. Van Heflin, the target of her obsession, is flawed, but not in a particularly damning way.
I think it's more of a psychological thriller than noir. Throughout the film you see her uneven descent into madness, and there's not anyone in particular to blame. Her husband tries to get her help, but no one understands what's happening until too late.
That's a direct contradiction of the noir construct.
The supporting cast is likewise wholesome. No one is full of greed, hate, lust, or anything unsavory. Her husband is caring widower and his kids are well-meaning. This ain't Mildred Pierce.
The real villain is arguably the mental health system, which hasn't improved much (in fact it's arguably worse) since 1947. That's a crime and a tragedy, but it isn't film noir.