THE SECRET FURY: I object! on the grounds of sheer preposterousness

Hollywood's never had any qualms about playing fast and loose with the realities of the judicial system if it got in the way of a good yarn but I've never seen anything quite as ludicrous as 1950's THE SECRET FURY.
RKO must have threatened Claudette Colbert with compromising photos (possibly of her face in right profile) to persuade her to star in this ridiculous melodrama about a woman driven mad by a marriage she can't remember.
She plays highly strung concert pianist Ellen Ewing whose wedding to dashing young(ish) architect David McLean (Robert Ryan) is halted mid-ceremony by a stranger claiming that she's already married to a Lucien Randall. Ellen insists he's lying but when she's recognised as Mrs Randall by the justice of the peace who performed the earlier ceremony, and the chambermaid at her honeymoon hotel, David insists they find Randall and confront him. When they track him down he insists on talking with his 'wife' alone but no sooner do they close the door than a shot rings out and David bursts in to find Randall dead, a revolver on the floor and a shocked Ellen unable to offer a plausible explanation of what just happened.
So far so good.
This is pretty standard thriller/drama territory.
It's at Ellen's trial for Randall's murder where things get seriously nonsensical.
Ellen's defence lawyer is her late father's best friend and guardian of the Ewing family affairs (which is about as close to having a fool for a lawyer as it's possible to get without actually defending yourself) while the prosecution is led by the local district attorney (Paul Kelly) who was also David's rival for Ellen's affections, and who acknowledges pre-trial that he has a conflict of interest (but his boss doesn't agree!).
And so the stage is set for a trial where both the defence and the prosecution can barely contain the urge to address the accused as 'Ellen, darling' and wild, legally totally inadmissible claims and accusations are hurled by both sides reducing Ellen to a screaming wreck and allowing her lawyer to change her plea to not guilty by reason of insanity.
It's at this point that you will - if you've not been completely distracted by the nonsense unfolding in front of you - figure out who the mastermind behind this evil plot really is. It's really not that difficult.
But what you'll never figure out in a million years is why he is doing what he does to poor Ellen. Preposterous doesn't even begin to describe his motive, but at least he has one. Director Mel Ferrer clearly hopes we'll be so overwhelmed by the climactic contrived explanation that we won't notice no one's even attempted to explain why Ellen 'forgot' to mention that this person was in the room with her at the moment that Randall was murdered.
THE SECRET FURY is no one's finest moment. I'm guessing Colbert took it because her star was starting to wane and she was grateful for the work, but she's too old and sophisticated to be convincing in the part. Ryan appears ill at ease in a colorless role which could have been played by any number of less talented B-list leading men. I'm a huge fan of his work but there was little to enjoy here.
Exasperating nonsense from start to finish THE SECRET FURY is prima facie evidence that not everything released during Hollywood's golden age is as precious as the name suggests. Some of it is as worthless as a rusty tin.