So I guess it is open for everyone's own interpretation what just happens in the end. I assumed it was meant to portray that he (Gene Hackman) thought that his wife hated him so much that she was framing him for the murders or committed the murders and that is why Hackman's character begins to confess to a crime he did not commit. Then again I read what a lot of people thought about the ending on a another movie site and their idea was that Hackman's character 'cracked' and was brainwashed into thinking he did the murders, but I don't think that makes any sense what with him being a hotshot lawyer and all. He would've been grilled in court so many times I imagine people in his profession would pretty much be the last people on earth to crack like that under police coercion.

Well, either way I feel the movie is a bit too longwinded for a lackluster ending like that.